CVE-2025-71070
published 2026-01-13CVE-2025-71070: In the Linux kernel, the following vulnerability has been resolved: ublk: clean up user copy references on ublk server exit If a ublk server process releases a…
PriorityP341high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.12%
2.2th percentile
In the Linux kernel, the following vulnerability has been resolved:
ublk: clean up user copy references on ublk server exit
If a ublk server process releases a ublk char device file, any requests
dispatched to the ublk server but not yet completed will retain a ref
value of UBLK_REFCOUNT_INIT. Before commit e63d2228ef83 ("ublk: simplify
aborting ublk request"), __ublk_fail_req() would decrement the reference
count before completing the failed request. However, that commit
optimized __ublk_fail_req() to call __ublk_complete_rq() directly
without decrementing the request reference count.
The leaked reference count incorrectly allows user copy and zero copy
operations on the completed ublk request. It also triggers the
WARN_ON_ONCE(refcount_read(&io->ref)) warnings in ublk_queue_reinit()
and ublk_deinit_queue().
Commit c5c5eb24ed61 ("ublk: avoid ublk_io_release() called after ublk
char dev is closed") already fixed the issue for ublk devices using
UBLK_F_SUPPORT_ZERO_COPY or UBLK_F_AUTO_BUF_REG. However, the reference
count leak also affects UBLK_F_USER_COPY, the other reference-counted
data copy mode. Fix the condition in ublk_check_and_reset_active_ref()
to include all reference-counted data copy modes. This ensures that any
ublk requests still owned by the ublk server when it exits have their
reference counts reset to 0.
Affected
20 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.18.3-1 (forky) | linux 6.18.3-1 (forky) |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | >= 6.14.6 < 6.15 | 6.15 |
| linux | linux | >= e63d2228ef831af36f963b3ab8604160cfff84c1 < 13456b4f1033d911f8bf3a0a1195656f293ba0f6 | 13456b4f1033d911f8bf3a0a1195656f293ba0f6 |
| linux | linux | >= e63d2228ef831af36f963b3ab8604160cfff84c1 < daa24603d9f0808929514ee62ced30052ca7221c | daa24603d9f0808929514ee62ced30052ca7221c |
| linux | linux_kernel | >= 0 < 6.18.3-1 | 6.18.3-1 |
| linux | linux_kernel | >= 6.15.0 < 6.18.3 | 6.18.3 |
| ubuntu | linux-aws | — | — |
| ubuntu | linux-aws-6.17 | — | — |
| ubuntu | linux-azure | — | — |
| ubuntu | linux-azure-6.17 | — | — |
| ubuntu | linux-gcp | — | — |
| ubuntu | linux-gcp-6.17 | — | — |
| ubuntu | linux-hwe-6.17 | — | — |
| ubuntu | linux-oem-6.17 | — | — |
| ubuntu | linux-oracle | — | — |
| ubuntu | linux-oracle-6.17 | — | — |
| ubuntu | linux-raspi | — | — |
| ubuntu | linux-realtime-6.17 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
vendor_ubuntu6.4MEDIUM
vendor_redhat3.3LOW
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Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 6.4
CVE-2025-71149 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel 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)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
-
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 6.4
CVE-2025-68781 [MEDIUM] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) 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)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
-
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-04-23·CVSS 6.4
CVE-2025-68801 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel 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)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
-
Ubuntu
Linux kernel (GCP) vulnerabilities
vendor_ubuntu·2026-04-17·CVSS 6.4
CVE-2025-68736 [MEDIUM] Linux kernel (GCP) vulnerabilities
Title: Linux kernel (GCP) 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)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI driv
Ubuntu
Linux kernel (Real-time) vulnerabilities
vendor_ubuntu·2026-04-17·CVSS 6.4
CVE-2025-68736 [MEDIUM] Linux kernel (Real-time) vulnerabilities
Title: Linux kernel (Real-time) 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)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACP
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-04-16·CVSS 6.4
CVE-2025-68736 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel 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)
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:
- MIPS architecture;
- PowerPC architecture;
- User-Mode Linux (UML);
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- ACPI drivers;
-
Red Hat
kernel: ublk: clean up user copy references on ublk server exit
vendor_redhat·2026-01-13·CVSS 3.3
CVE-2025-71070 [LOW] CWE-911 kernel: ublk: clean up user copy references on ublk server exit
kernel: ublk: clean up user copy references on ublk server exit
In the Linux kernel, the following vulnerability has been resolved:
ublk: clean up user copy references on ublk server exit
If a ublk server process releases a ublk char device file, any requests
dispatched to the ublk server but not yet completed will retain a ref
value of UBLK_REFCOUNT_INIT. Before commit e63d2228ef83 ("ublk: simplify
aborting ublk request"), __ublk_fail_req() would decrement the reference
count before completing the failed request. However, that commit
optimized __ublk_fail_req() to call __ublk_complete_rq() directly
without decrementing the request reference count.
The leaked reference count incorrectly allows user copy and zero copy
operations on the completed ublk request. It also triggers the
WARN_ON_O
Debian
CVE-2025-71070: linux - In the Linux kernel, the following vulnerability has been resolved: ublk: clean...
vendor_debian·2025
CVE-2025-71070 [LOW] CVE-2025-71070: linux - In the Linux kernel, the following vulnerability has been resolved: ublk: clean...
In the Linux kernel, the following vulnerability has been resolved: ublk: clean up user copy references on ublk server exit If a ublk server process releases a ublk char device file, any requests dispatched to the ublk server but not yet completed will retain a ref value of UBLK_REFCOUNT_INIT. Before commit e63d2228ef83 ("ublk: simplify aborting ublk request"), __ublk_fail_req() would decrement the reference count before completing the failed request. However, that commit optimized __ublk_fail_req() to call __ublk_complete_rq() directly without decrementing the request reference count. The leaked reference count incorrectly allows user copy and zero copy operations on the completed ublk request. It also triggers the WARN_ON_ONCE(refcount_read(&io->ref)) warnings in ublk_queue_reinit() and
OSV
ublk: clean up user copy references on ublk server exit
osv·2026-01-13
CVE-2025-71070 ublk: clean up user copy references on ublk server exit
ublk: clean up user copy references on ublk server exit
In the Linux kernel, the following vulnerability has been resolved:
ublk: clean up user copy references on ublk server exit
If a ublk server process releases a ublk char device file, any requests
dispatched to the ublk server but not yet completed will retain a ref
value of UBLK_REFCOUNT_INIT. Before commit e63d2228ef83 ("ublk: simplify
aborting ublk request"), __ublk_fail_req() would decrement the reference
count before completing the failed request. However, that commit
optimized __ublk_fail_req() to call __ublk_complete_rq() directly
without decrementing the request reference count.
The leaked reference count incorrectly allows user copy and zero copy
operations on the completed ublk request. It also triggers the
WARN_ON_ONCE(re
GHSA
GHSA-p797-qv57-j9x8: In the Linux kernel, the following vulnerability has been resolved:
ublk: clean up user copy references on ublk server exit
If a ublk server process
ghsa_unreviewed·2026-01-13
CVE-2025-71070 GHSA-p797-qv57-j9x8: In the Linux kernel, the following vulnerability has been resolved:
ublk: clean up user copy references on ublk server exit
If a ublk server process
In the Linux kernel, the following vulnerability has been resolved:
ublk: clean up user copy references on ublk server exit
If a ublk server process releases a ublk char device file, any requests
dispatched to the ublk server but not yet completed will retain a ref
value of UBLK_REFCOUNT_INIT. Before commit e63d2228ef83 ("ublk: simplify
aborting ublk request"), __ublk_fail_req() would decrement the reference
count before completing the failed request. However, that commit
optimized __ublk_fail_req() to call __ublk_complete_rq() directly
without decrementing the request reference count.
The leaked reference count incorrectly allows user copy and zero copy
operations on the completed ublk request. It also triggers the
WARN_ON_ONCE(refcount_read(&io->ref)) warnings in ublk_queue_reinit()
an
OSV
CVE-2025-71070: In the Linux kernel, the following vulnerability has been resolved: ublk: clean up user copy references on ublk server exit If a ublk server process r
osv·2026-01-13
CVE-2025-71070 CVE-2025-71070: In the Linux kernel, the following vulnerability has been resolved: ublk: clean up user copy references on ublk server exit If a ublk server process r
In the Linux kernel, the following vulnerability has been resolved: ublk: clean up user copy references on ublk server exit If a ublk server process releases a ublk char device file, any requests dispatched to the ublk server but not yet completed will retain a ref value of UBLK_REFCOUNT_INIT. Before commit e63d2228ef83 ("ublk: simplify aborting ublk request"), __ublk_fail_req() would decrement the reference count before completing the failed request. However, that commit optimized __ublk_fail_req() to call __ublk_complete_rq() directly without decrementing the request reference count. The leaked reference count incorrectly allows user copy and zero copy operations on the completed ublk request. It also triggers the WARN_ON_ONCE(refcount_read(&io->ref)) warnings in ublk_queue_reinit() and
No detection rules found.
No public exploits indexed.
2026-01-13
Published