CVE-2025-39977
published 2025-10-15CVE-2025-39977: In the Linux kernel, the following vulnerability has been resolved: futex: Prevent use-after-free during requeue-PI syzbot managed to trigger the following…
PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.14%
3.8th percentile
In the Linux kernel, the following vulnerability has been resolved: futex: Prevent use-after-free during requeue-PI syzbot managed to trigger the following race: T1 T2 futex_wait_requeue_pi() futex_do_wait() schedule() futex_requeue() futex_proxy_trylock_atomic() futex_requeue_pi_prepare() requeue_pi_wake_futex() futex_requeue_pi_complete() /* preempt */ * timeout/ signal wakes T1 * futex_requeue_pi_wakeup_sync() // Q_REQUEUE_PI_LOCKED futex_hash_put() // back to userland, on stack futex_q is garbage /* back */ wake_up_state(q->task, TASK_NORMAL); In this scenario futex_wait_requeue_pi() is able to leave without using futex_q::lock_ptr for synchronization. This can be prevented by reading futex_q::task before updating the futex_q::requeue_state. A reference on the task_struct is not needed because requeue_pi_wake_futex() is invoked with a spinlock_t held which implies a RCU read section. Even if T1 terminates immediately after, the task_struct will remain valid during T2's wake_up_state(). A READ_ONCE on futex_q::task before futex_requeue_pi_complete() is enough because it ensures that the variable is read before the state is updated. Read futex_q::task before updating the requeue state, use it for the following wakeup.
Affected
19 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.158-1 (bookworm) | linux 6.1.158-1 (bookworm) |
| debian | linux-6.1 | < linux 6.1.158-1 (bookworm) | linux 6.1.158-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 07d91ef510fb16a2e0ca7453222105835b7ba3b8 < cb5d19a61274b51b49601214a87af573b43d60fa | cb5d19a61274b51b49601214a87af573b43d60fa |
| linux | linux | >= 07d91ef510fb16a2e0ca7453222105835b7ba3b8 < 348736955ed6ca6e99ca24b93b1d3fbfe352c181 | 348736955ed6ca6e99ca24b93b1d3fbfe352c181 |
| linux | linux | >= 07d91ef510fb16a2e0ca7453222105835b7ba3b8 < a170b9c0dde83312b8b58ccc91509c7c15711641 | a170b9c0dde83312b8b58ccc91509c7c15711641 |
| linux | linux | >= 07d91ef510fb16a2e0ca7453222105835b7ba3b8 < d824b2dbdcfe3c390278dd9652ea526168ef6850 | d824b2dbdcfe3c390278dd9652ea526168ef6850 |
| linux | linux | >= 07d91ef510fb16a2e0ca7453222105835b7ba3b8 < b549113738e8c751b613118032a724b772aa83f2 | b549113738e8c751b613118032a724b772aa83f2 |
| linux | linux_kernel | >= 0 < 6.1.158-1 | 6.1.158-1 |
| linux | linux_kernel | >= 0 < 6.12.57-1 | 6.12.57-1 |
| linux | linux_kernel | >= 0 < 6.16.10-1 | 6.16.10-1 |
| linux | linux_kernel | >= 0 < 6.8.0-106.106 | 6.8.0-106.106 |
| linux | linux_kernel | >= 5.15.0 < 6.1.155 | 6.1.155 |
| linux | linux_kernel | >= 6.13.0 < 6.16.10 | 6.16.10 |
| linux | linux_kernel | >= 6.2.0 < 6.6.109 | 6.6.109 |
| linux | linux_kernel | >= 6.7.0 < 6.12.50 | 6.12.50 |
| msrc | azl3_kernel_6.6.104.2-4_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.96.2-2_on_azure_linux_3.0 | — | — |
| ubuntu | linux-xilinx | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv3.2LOW
vendor_msrc7.8HIGH
vendor_ubuntu7.8HIGH
vendor_redhat4.7MEDIUM
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Ubuntu
Linux kernel (Xilinx) vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 6.4
CVE-2025-68288 [MEDIUM] Linux kernel (Xilinx) vulnerabilities
Title: Linux kernel (Xilinx) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality. (CVE-2024-36347)
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation,
Ubuntu
Linux kernel (Azure FIPS) vulnerabilities
vendor_ubuntu·2026-04-09·CVSS 7.8
CVE-2025-21833 [HIGH] Linux kernel (Azure FIPS) vulnerabilities
Title: Linux kernel (Azure FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23406, CVE-2026-23407,
CVE-2026-23408, CVE-2026-23409, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-04-01
CVE-2025-40301 Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architect
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-03-25·CVSS 3.2
CVE-2025-40068 [LOW] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
It was discovered that improper initialization of CPU cache memory could
allow a local attacker with hypervisor access to overwrite SEV-SNP guest
memory resulting in loss of data integrity. (CVE-2024-36331)
Oleksii Oleksenko, Cedric Fournet, Jana Hofmann, Boris Köpf, Stavros Volos,
and Flavien Solt discovered that
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-03-25
CVE-2025-40245 Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
-
Ubuntu
Linux kernel (AWS) vulnerabilities
vendor_ubuntu·2026-03-23
CVE-2025-40068 Linux kernel (AWS) vulnerabilities
Title: Linux kernel (AWS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Su
Ubuntu
Linux kernel (Real-time) vulnerabilities
vendor_ubuntu·2026-03-17
CVE-2025-40245 Linux kernel (Real-time) vulnerabilities
Title: Linux kernel (Real-time) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture
Ubuntu
Linux kernel (FIPS) vulnerabilities
vendor_ubuntu·2026-03-16
CVE-2025-40068 Linux kernel (FIPS) vulnerabilities
Title: Linux kernel (FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- S
Ubuntu
Linux kernel (NVIDIA) vulnerabilities
vendor_ubuntu·2026-03-16
CVE-2025-40245 Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
-
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-03-16
CVE-2025-39981 Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Spar
Red Hat
kernel: futex: Prevent use-after-free during requeue-PI
vendor_redhat·2025-10-15·CVSS 4.7
CVE-2025-39977 [MEDIUM] CWE-416 kernel: futex: Prevent use-after-free during requeue-PI
kernel: futex: Prevent use-after-free during requeue-PI
In the Linux kernel, the following vulnerability has been resolved:
futex: Prevent use-after-free during requeue-PI
syzbot managed to trigger the following race:
T1 T2
futex_wait_requeue_pi()
futex_do_wait()
schedule()
futex_requeue()
futex_proxy_trylock_atomic()
futex_requeue_pi_prepare()
requeue_pi_wake_futex()
futex_requeue_pi_complete()
/* preempt */
* timeout/ signal wakes T1 *
futex_requeue_pi_wakeup_sync() // Q_REQUEUE_PI_LOCKED
futex_hash_put()
// back to userland, on stack futex_q is garbage
/* back */
wake_up_state(q->task, TASK_NORMAL);
In this scenario futex_wait_requeue_pi() is able to leave without using
futex_q::lock_ptr for synchronization.
This can be prevented by reading futex_q::task before updating the
futex_q::re
Microsoft
futex: Prevent use-after-free during requeue-PI
vendor_msrc·2025-10-14·CVSS 7.8
CVE-2025-39977 [HIGH] futex: Prevent use-after-free during requeue-PI
futex: Prevent use-after-free during requeue-PI
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
Linux: Linux
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: https://learn.microso
Debian
CVE-2025-39977: linux - In the Linux kernel, the following vulnerability has been resolved: futex: Prev...
vendor_debian·2025
CVE-2025-39977 CVE-2025-39977: linux - In the Linux kernel, the following vulnerability has been resolved: futex: Prev...
In the Linux kernel, the following vulnerability has been resolved: futex: Prevent use-after-free during requeue-PI syzbot managed to trigger the following race: T1 T2 futex_wait_requeue_pi() futex_do_wait() schedule() futex_requeue() futex_proxy_trylock_atomic() futex_requeue_pi_prepare() requeue_pi_wake_futex() futex_requeue_pi_complete() /* preempt */ * timeout/ signal wakes T1 * futex_requeue_pi_wakeup_sync() // Q_REQUEUE_PI_LOCKED futex_hash_put() // back to userland, on stack futex_q is garbage /* back */ wake_up_state(q->task, TASK_NORMAL); In this scenario futex_wait_requeue_pi() is able to leave without using futex_q::lock_ptr for synchronization. This can be prevented by reading futex_q::task before updating the futex_q::requeue_state. A reference on the task_struct is not needed
OSV
linux-raspi, linux-raspi-realtime vulnerabilities
osv·2026-04-01
linux-raspi, linux-raspi-realtime vulnerabilities
linux-raspi, linux-raspi-realtime vulnerabilities
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- User-Mode Linux (UML);
- x86 archi
OSV
linux-azure-6.8 vulnerabilities
osv·2026-03-25·CVSS 3.2
[LOW] linux-azure-6.8 vulnerabilities
linux-azure-6.8 vulnerabilities
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
It was discovered that improper initialization of CPU cache memory could
allow a local attacker with hypervisor access to overwrite SEV-SNP guest
memory resulting in loss of data integrity. (CVE-2024-36331)
Oleksii Oleksenko, Cedric Fournet, Jana Hofmann, Boris Köpf, Stavros Volos,
and Flavien Solt discovered that some AMD processors may allow an attacker
to infer data from previous stores,
OSV
linux-azure vulnerabilities
osv·2026-03-25
linux-azure vulnerabilities
linux-azure vulnerabilities
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Xtensa arch
OSV
linux-aws-6.8 vulnerabilities
osv·2026-03-23
linux-aws-6.8 vulnerabilities
linux-aws-6.8 vulnerabilities
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Xtensa ar
OSV
linux-realtime, linux-realtime-6.8 vulnerabilities
osv·2026-03-17
linux-realtime, linux-realtime-6.8 vulnerabilities
linux-realtime, linux-realtime-6.8 vulnerabilities
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- User-Mode Linux (UML);
- x86 arch
OSV
linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency vulnerabilities
osv·2026-03-16
linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency vulnerabilities
linux-nvidia, linux-nvidia-6.8, linux-nvidia-lowlatency vulnerabilities
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- User-Mode Li
OSV
linux-fips, linux-aws-fips, linux-gcp-fips vulnerabilities
osv·2026-03-16
linux-fips, linux-aws-fips, linux-gcp-fips vulnerabilities
linux-fips, linux-aws-fips, linux-gcp-fips vulnerabilities
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Nios II architecture;
- PA-RISC architecture;
- RISC-V architecture;
- S390 architecture;
- Sun Sparc architecture;
- User-Mode Linux (UML);
-
OSV
linux, linux-aws, linux-gcp, linux-gcp-6.8, linux-gke, linux-gkeop, linux-hwe-6.8, linux-ibm, linux-ibm-6.8, linux-lowlatency, linux-lowlatency-hwe-6.8, linux-oracle, linux-oracle-6.8 vulnerabilities
osv·2026-03-16
linux, linux-aws, linux-gcp, linux-gcp-6.8, linux-gke, linux-gkeop, linux-hwe-6.8, linux-ibm, linux-ibm-6.8, linux-lowlatency, linux-lowlatency-hwe-6.8, linux-oracle, linux-oracle-6.8 vulnerabilities
linux, linux-aws, linux-gcp, linux-gcp-6.8, linux-gke, linux-gkeop, linux-hwe-6.8, linux-ibm, linux-ibm-6.8, linux-lowlatency, linux-lowlatency-hwe-6.8, linux-oracle, linux-oracle-6.8 vulnerabilities
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- MIPS architecture;
- Ni
OSV
CVE-2025-39977: In the Linux kernel, the following vulnerability has been resolved: futex: Prevent use-after-free during requeue-PI syzbot managed to trigger the foll
osv·2025-10-15
CVE-2025-39977 CVE-2025-39977: In the Linux kernel, the following vulnerability has been resolved: futex: Prevent use-after-free during requeue-PI syzbot managed to trigger the foll
In the Linux kernel, the following vulnerability has been resolved: futex: Prevent use-after-free during requeue-PI syzbot managed to trigger the following race: T1 T2 futex_wait_requeue_pi() futex_do_wait() schedule() futex_requeue() futex_proxy_trylock_atomic() futex_requeue_pi_prepare() requeue_pi_wake_futex() futex_requeue_pi_complete() /* preempt */ * timeout/ signal wakes T1 * futex_requeue_pi_wakeup_sync() // Q_REQUEUE_PI_LOCKED futex_hash_put() // back to userland, on stack futex_q is garbage /* back */ wake_up_state(q->task, TASK_NORMAL); In this scenario futex_wait_requeue_pi() is able to leave without using futex_q::lock_ptr for synchronization. This can be prevented by reading futex_q::task before updating the futex_q::requeue_state. A reference on the task_struct is not needed
GHSA
GHSA-56h7-2ch6-v472: In the Linux kernel, the following vulnerability has been resolved:
futex: Prevent use-after-free during requeue-PI
syzbot managed to trigger the fo
ghsa_unreviewed·2025-10-15
CVE-2025-39977 GHSA-56h7-2ch6-v472: In the Linux kernel, the following vulnerability has been resolved:
futex: Prevent use-after-free during requeue-PI
syzbot managed to trigger the fo
In the Linux kernel, the following vulnerability has been resolved:
futex: Prevent use-after-free during requeue-PI
syzbot managed to trigger the following race:
T1 T2
futex_wait_requeue_pi()
futex_do_wait()
schedule()
futex_requeue()
futex_proxy_trylock_atomic()
futex_requeue_pi_prepare()
requeue_pi_wake_futex()
futex_requeue_pi_complete()
/* preempt */
* timeout/ signal wakes T1 *
futex_requeue_pi_wakeup_sync() // Q_REQUEUE_PI_LOCKED
futex_hash_put()
// back to userland, on stack futex_q is garbage
/* back */
wake_up_state(q->task, TASK_NORMAL);
In this scenario futex_wait_requeue_pi() is able to leave without using
futex_q::lock_ptr for synchronization.
This can be prevented by reading futex_q::task before updating the
futex_q::requeue_state. A reference on the task_struct is n
OSV
futex: Prevent use-after-free during requeue-PI
osv·2025-10-15
CVE-2025-39977 futex: Prevent use-after-free during requeue-PI
futex: Prevent use-after-free during requeue-PI
In the Linux kernel, the following vulnerability has been resolved:
futex: Prevent use-after-free during requeue-PI
syzbot managed to trigger the following race:
T1 T2
futex_wait_requeue_pi()
futex_do_wait()
schedule()
futex_requeue()
futex_proxy_trylock_atomic()
futex_requeue_pi_prepare()
requeue_pi_wake_futex()
futex_requeue_pi_complete()
/* preempt */
* timeout/ signal wakes T1 *
futex_requeue_pi_wakeup_sync() // Q_REQUEUE_PI_LOCKED
futex_hash_put()
// back to userland, on stack futex_q is garbage
/* back */
wake_up_state(q->task, TASK_NORMAL);
In this scenario futex_wait_requeue_pi() is able to leave without using
futex_q::lock_ptr for synchronization.
This can be prevented by reading futex_q::task before updating the
futex_q::r
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://git.kernel.org/stable/c/348736955ed6ca6e99ca24b93b1d3fbfe352c181https://git.kernel.org/stable/c/a170b9c0dde83312b8b58ccc91509c7c15711641https://git.kernel.org/stable/c/b549113738e8c751b613118032a724b772aa83f2https://git.kernel.org/stable/c/cb5d19a61274b51b49601214a87af573b43d60fahttps://git.kernel.org/stable/c/d824b2dbdcfe3c390278dd9652ea526168ef6850https://cert-portal.siemens.com/productcert/html/ssa-019113.htmlhttps://cert-portal.siemens.com/productcert/html/ssa-082556.html
2025-10-15
Published