CVE-2026-64439
published 2026-07-25CVE-2026-64439: In the Linux kernel, the following vulnerability has been resolved: crypto: krb5 - filter out async aead implementations at alloc krb5_aead_encrypt()…
PriorityP350critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.63%
48.9th percentile
In the Linux kernel, the following vulnerability has been resolved:
crypto: krb5 - filter out async aead implementations at alloc
krb5_aead_encrypt(), krb5_aead_decrypt() in rfc3961_simplified.c and
rfc8009_encrypt(), rfc8009_decrypt() in rfc8009_aes2.c set a NULL
completion callback and treat any negative return from
crypto_aead_{encrypt,decrypt}() as terminal, falling through to
kfree_sensitive(buffer). When the encrypt_name resolves to an
async AEAD instance the request returns -EINPROGRESS, the buffer
is freed while the backend's worker still holds a pointer, and the
worker dereferences the freed slab on completion.
KASAN report under UML+SLUB with a synthetic async aead backend
bound to krb5->encrypt_name:
BUG: KASAN: slab-use-after-free in t5_stub_complete+0x7d/0xc7
The helpers were written synchronously, so filter the async
instances out at allocation time instead of plumbing
crypto_wait_req() through every call site.
Reachable via net/rxrpc/rxgk.c, fs/afs/cm_security.c and
net/ceph/crypto.c on systems with an async AEAD provider bound to
the krb5 enctype name.
Affected
24 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= 00244da40f7821b242c4612428d4192230dba27f < ef6feb77e2d91761427c5b773edc9c97e1b706ad | ef6feb77e2d91761427c5b773edc9c97e1b706ad |
| linux | linux | >= 00244da40f7821b242c4612428d4192230dba27f < 2b7bd6dccff14b8b632c5244f1fd506918077221 | 2b7bd6dccff14b8b632c5244f1fd506918077221 |
| linux | linux | >= 00244da40f7821b242c4612428d4192230dba27f < 6c9dddeb582fde005360f4fe02c760d45ca05fb5 | 6c9dddeb582fde005360f4fe02c760d45ca05fb5 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 6.15 < 6.18.39 | 6.18.39 |
| linux | linux_kernel | >= 6.19 < 7.1.4 | 7.1.4 |
| ubuntu | linux | — | — |
| ubuntu | linux-aws | — | — |
| ubuntu | linux-aws-7.0 | — | — |
| ubuntu | linux-azure | — | — |
| ubuntu | linux-azure-7.0 | — | — |
| ubuntu | linux-gcp | — | — |
| ubuntu | linux-gcp-7.0 | — | — |
| ubuntu | linux-gke | — | — |
| ubuntu | linux-hwe-7.0 | — | — |
| ubuntu | linux-ibm | — | — |
| ubuntu | linux-nvidia-7.0 | — | — |
| ubuntu | linux-nvidia-bos | — | — |
| ubuntu | linux-oem-7.0 | — | — |
| ubuntu | linux-oracle | — | — |
| ubuntu | linux-oracle-7.0 | — | — |
| ubuntu | linux-raspi | — | — |
| ubuntu | linux-realtime | — | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vendor_redhat9.8CRITICAL
vendor_ubuntu9.1CRITICAL
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Ubuntu
Linux kernel (Oracle) vulnerabilities
vendor_ubuntu·2026-09-29·CVSS 9.1
CVE-2026-64191 [CRITICAL] Linux kernel (Oracle) vulnerabilities
Title: Linux kernel (Oracle) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
Several security issues were d
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-09-22·CVSS 9.1
CVE-2026-63869 [CRITICAL] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390 architecture;
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-09-22·CVSS 9.1
CVE-2026-52938 [CRITICAL] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
Several security issues were di
Ubuntu
Linux kernel (NVIDIA BaseOS) vulnerabilities
vendor_ubuntu·2026-09-22
CVE-2026-64504 Linux kernel (NVIDIA BaseOS) vulnerabilities
Title: Linux kernel (NVIDIA BaseOS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
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:
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- ARM64 architecture;
- RISC-V architecture;
- S390 architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- Intel NPU Driver;
- ACPI drivers;
- Android drivers;
- Drivers core;
- Compressed RAM block device driver;
- Bluetooth drivers;
- Character device driver;
- Hardware random number generator core;
- CPU frequency scaling framework;
- Hardware crypto device drivers
Ubuntu
Linux kernel (IBM) vulnerabilities
vendor_ubuntu·2026-09-21·CVSS 9.1
CVE-2026-63869 [CRITICAL] Linux kernel (IBM) vulnerabilities
Title: Linux kernel (IBM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390 architec
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-09-18·CVSS 9.1
CVE-2026-64504 [CRITICAL] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390
Ubuntu
Linux kernel (NVIDIA) vulnerabilities
vendor_ubuntu·2026-09-15
CVE-2026-63869 Linux kernel (NVIDIA) vulnerabilities
Title: Linux kernel (NVIDIA) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
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:
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- ARM64 architecture;
- RISC-V architecture;
- S390 architecture;
- x86 architecture;
- Block layer subsystem;
- Cryptographic API;
- Compute Acceleration Framework;
- Intel NPU Driver;
- ACPI drivers;
- Android drivers;
- Drivers core;
- Compressed RAM block device driver;
- Bluetooth drivers;
- Character device driver;
- Hardware random number generator core;
- CPU frequency scaling framework;
- Hardware crypto device drivers;
- Buf
Ubuntu
Linux kernel (GCP) vulnerabilities
vendor_ubuntu·2026-09-07·CVSS 9.1
CVE-2026-52938 [CRITICAL] Linux kernel (GCP) vulnerabilities
Title: Linux kernel (GCP) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
It was discovered that some AMD Zen 2 processors did not properly isolate
shared resources in the operation cache. A local attacker could possibly
use this issue to corrupt instructions executed at a higher privilege
level, resulting in privilege escalation. (CVE-2025-54518)
Several security issues were disc
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-09-07·CVSS 9.1
CVE-2026-64504 [CRITICAL] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390 architecture;
Ubuntu
Linux kernel (OEM) vulnerabilities
vendor_ubuntu·2026-09-07·CVSS 9.1
CVE-2026-63869 [CRITICAL] Linux kernel (OEM) vulnerabilities
Title: Linux kernel (OEM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some Arm processors could complete a broadcast
translation lookaside buffer (TLB) invalidation before memory writes made
through the invalidated translation were globally observed. A local
attacker could possibly use this to write to memory after permission to do
so had been revoked, bypassing memory protections or escalating privileges.
(CVE-2025-10263)
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;
- User-space API (UAPI);
- Kernel build system;
- ARM32 architecture;
- RISC-V architecture;
- S390 architec
Red Hat
kernel: crypto: krb5 - filter out async aead implementations at alloc
vendor_redhat·2026-07-25·CVSS 9.8
CVE-2026-64439 [CRITICAL] CWE-825 kernel: crypto: krb5 - filter out async aead implementations at alloc
kernel: crypto: krb5 - filter out async aead implementations at alloc
A flaw was found in the Linux kernel's Kerberos 5 (krb5) cryptography module. This use-after-free vulnerability occurs when an asynchronous Authenticated Encryption with Associated Data (AEAD) instance is used. The system prematurely frees a memory buffer while a backend process still holds a pointer to it, leading to the process attempting to access the freed memory. This can result in a system crash, causing a Denial of Service (DoS).
Package: kernel (Red Hat Enterprise Linux 10) - Affected
Package: kernel (Red Hat Enterprise Linux 6) - Not affected
Package: kernel (Red Hat Enterprise Linux 7) - Not affected
Package: kernel-rt (Red Hat Enterprise Linux 7) - Not affected
Package: kernel (Red Hat Enterprise Linux 8
VulDB
Linux Kernel up to 6.18.38/7.1.3 Crypto rfc3961_simplified.c use after free
vuldb·2026-07-25
CVE-2026-64439 Linux Kernel up to 6.18.38/7.1.3 Crypto rfc3961_simplified.c use after free
A vulnerability marked as very critical has been reported in Linux Kernel up to 6.18.38/7.1.3. This issue affects the function krb5_aead_encrypt/krb5_aead_decrypt/rfc8009_encrypt/rfc8009_decrypt of the file rfc3961_simplified.c of the component Crypto. This manipulation causes use after free.
This vulnerability appears as CVE-2026-64439. The attack may be initiated remotely. There is no available exploit.
It is suggested to upgrade the affected component.
GHSA
In the Linux kernel, the following vulnerability has been resolved: crypto: krb5 - filter out async aead implementations at alloc krb5_aead_encrypt(), krb5_aead_decrypt() in rfc3961_simplified.c and
ghsa_unreviewed·2026-07-25
CVE-2026-64439 In the Linux kernel, the following vulnerability has been resolved: crypto: krb5 - filter out async aead implementations at alloc krb5_aead_encrypt(), krb5_aead_decrypt() in rfc3961_simplified.c and
In the Linux kernel, the following vulnerability has been resolved:
crypto: krb5 - filter out async aead implementations at alloc
krb5_aead_encrypt(), krb5_aead_decrypt() in rfc3961_simplified.c and
rfc8009_encrypt(), rfc8009_decrypt() in rfc8009_aes2.c set a NULL
completion callback and treat any negative return from
crypto_aead_{encrypt,decrypt}() as terminal, falling through to
kfree_sensitive(buffer). When the encrypt_name resolves to an
async AEAD instance the request returns -EINPROGRESS, the buffer
is freed while the backend's worker still holds a pointer, and the
worker dereferences the freed slab on completion.
KASAN report under UML+SLUB with a synthetic async aead backend
bound to krb5->encrypt_name:
BUG: KASAN: slab-use-after-free in t5_stub_complete+0x7d/0xc7
The helpers
No detection rules found.
No public exploits indexed.
2026-07-25
Published