CVE-2025-21893
published 2025-03-31CVE-2025-21893: In the Linux kernel, the following vulnerability has been resolved: keys: Fix UAF in key_put() Once a key's reference count has been reduced to 0, the garbage…
PriorityP336high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.18%
8.0th percentile
In the Linux kernel, the following vulnerability has been resolved:
keys: Fix UAF in key_put()
Once a key's reference count has been reduced to 0, the garbage collector
thread may destroy it at any time and so key_put() is not allowed to touch
the key after that point. The most key_put() is normally allowed to do is
to touch key_gc_work as that's a static global variable.
However, in an effort to speed up the reclamation of quota, this is now
done in key_put() once the key's usage is reduced to 0 - but now the code
is looking at the key after the deadline, which is forbidden.
Fix this by using a flag to indicate that a key can be gc'd now rather than
looking at the key's refcount in the garbage collector.
Affected
10 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.12.21-1 (forky) | linux 6.12.21-1 (forky) |
| linux | linux | — | — |
| linux | linux | >= 9578e327b2b4935a25d49e3891b8fcca9b6c10c6 < 6afe2ea2daec156bd94ad2c5a6f4f4c48240dcd3 | 6afe2ea2daec156bd94ad2c5a6f4f4c48240dcd3 |
| linux | linux | >= 9578e327b2b4935a25d49e3891b8fcca9b6c10c6 < f6a3cf833188e897c97028cd7b926e3f2cb1a8c0 | f6a3cf833188e897c97028cd7b926e3f2cb1a8c0 |
| linux | linux | >= 9578e327b2b4935a25d49e3891b8fcca9b6c10c6 < 75845c6c1a64483e9985302793dbf0dfa5f71e32 | 75845c6c1a64483e9985302793dbf0dfa5f71e32 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.12.21-1 | 6.12.21-1 |
| linux | linux_kernel | >= 0 < 6.12.21-1 | 6.12.21-1 |
| linux | linux_kernel | >= 6.10 < 6.12.21 | 6.12.21 |
| linux | linux_kernel | >= 6.13 < 6.13.9 | 6.13.9 |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8LOW
vendor_redhat7.8HIGH
vendor_ubuntu5.9MEDIUM
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OSV
linux-azure, linux-azure-6.11 vulnerabilities
osv·2025-07-08·CVSS 5.9
CVE-2025-2312 [MEDIUM] linux-azure, linux-azure-6.11 vulnerabilities
linux-azure, linux-azure-6.11 vulnerabilities
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- x86 architecture;
- Compute Acceleration Framework;
- ACPI drivers;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bus devices;
- AMD CDX bus driver;
- Clock framework and drivers;
- DMA engine subsystem;
- DPLL subsystem;
- Qualcomm firmware driv
OSV
linux-lowlatency, linux-lowlatency-hwe-6.11 vulnerabilities
osv·2025-07-04·CVSS 5.9
CVE-2025-2312 [MEDIUM] linux-lowlatency, linux-lowlatency-hwe-6.11 vulnerabilities
linux-lowlatency, linux-lowlatency-hwe-6.11 vulnerabilities
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- x86 architecture;
- Compute Acceleration Framework;
- ACPI drivers;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bus devices;
- AMD CDX bus driver;
- Clock framework and drivers;
- DMA engine subsystem;
- DPLL subsystem;
- Qualcomm
OSV
linux-oem-6.11 vulnerabilities
osv·2025-06-30·CVSS 5.9
CVE-2025-2312 [MEDIUM] linux-oem-6.11 vulnerabilities
linux-oem-6.11 vulnerabilities
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- x86 architecture;
- Compute Acceleration Framework;
- ACPI drivers;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bus devices;
- AMD CDX bus driver;
- Clock framework and drivers;
- DMA engine subsystem;
- DPLL subsystem;
- Qualcomm firmware drivers;
- GPIO sub
OSV
linux, linux-aws, linux-gcp, linux-gcp-6.11, linux-hwe-6.11, linux-oracle, linux-raspi, linux-realtime vulnerabilities
osv·2025-06-30·CVSS 5.9
CVE-2025-2312 [MEDIUM] linux, linux-aws, linux-gcp, linux-gcp-6.11, linux-hwe-6.11, linux-oracle, linux-raspi, linux-realtime vulnerabilities
linux, linux-aws, linux-gcp, linux-gcp-6.11, linux-hwe-6.11, linux-oracle, linux-raspi, linux-realtime vulnerabilities
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- x86 architecture;
- Compute Acceleration Framework;
- ACPI drivers;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bus devices;
- AMD CDX bus driver;
- Clock framework and dr
GHSA
GHSA-prxc-p2g7-m92v: In the Linux kernel, the following vulnerability has been resolved:
keys: Fix UAF in key_put()
Once a key's reference count has been reduced to 0, t
ghsa_unreviewed·2025-03-31
CVE-2025-21893 [HIGH] CWE-416 GHSA-prxc-p2g7-m92v: In the Linux kernel, the following vulnerability has been resolved:
keys: Fix UAF in key_put()
Once a key's reference count has been reduced to 0, t
In the Linux kernel, the following vulnerability has been resolved:
keys: Fix UAF in key_put()
Once a key's reference count has been reduced to 0, the garbage collector
thread may destroy it at any time and so key_put() is not allowed to touch
the key after that point. The most key_put() is normally allowed to do is
to touch key_gc_work as that's a static global variable.
However, in an effort to speed up the reclamation of quota, this is now
done in key_put() once the key's usage is reduced to 0 - but now the code
is looking at the key after the deadline, which is forbidden.
Fix this by using a flag to indicate that a key can be gc'd now rather than
looking at the key's refcount in the garbage collector.
OSV
CVE-2025-21893: In the Linux kernel, the following vulnerability has been resolved: keys: Fix UAF in key_put() Once a key's reference count has been reduced to 0, the
osv·2025-03-31·CVSS 7.8
CVE-2025-21893 [HIGH] CVE-2025-21893: In the Linux kernel, the following vulnerability has been resolved: keys: Fix UAF in key_put() Once a key's reference count has been reduced to 0, the
In the Linux kernel, the following vulnerability has been resolved: keys: Fix UAF in key_put() Once a key's reference count has been reduced to 0, the garbage collector thread may destroy it at any time and so key_put() is not allowed to touch the key after that point. The most key_put() is normally allowed to do is to touch key_gc_work as that's a static global variable. However, in an effort to speed up the reclamation of quota, this is now done in key_put() once the key's usage is reduced to 0 - but now the code is looking at the key after the deadline, which is forbidden. Fix this by using a flag to indicate that a key can be gc'd now rather than looking at the key's refcount in the garbage collector.
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2025-07-08·CVSS 5.9
CVE-2025-22095 [MEDIUM] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- x86 architecture;
- Compute Acceleration Framework;
- ACPI drivers;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bus devices;
- AMD CDX bus driver;
- Clock framework and drivers;
-
Ubuntu
Linux kernel (Low Latency) vulnerabilities
vendor_ubuntu·2025-07-04·CVSS 5.9
CVE-2025-22080 [MEDIUM] Linux kernel (Low Latency) vulnerabilities
Title: Linux kernel (Low Latency) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- x86 architecture;
- Compute Acceleration Framework;
- ACPI drivers;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bus devices;
- AMD CDX bus driver;
- Clock framework and drive
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2025-06-30·CVSS 5.9
CVE-2025-22080 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- x86 architecture;
- Compute Acceleration Framework;
- ACPI drivers;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bus devices;
- AMD CDX bus driver;
- Clock framework and drivers;
- DMA engi
Ubuntu
Linux kernel (OEM) vulnerabilities
vendor_ubuntu·2025-06-30·CVSS 5.9
CVE-2025-22070 [MEDIUM] Linux kernel (OEM) vulnerabilities
Title: Linux kernel (OEM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the CIFS network file system implementation in the
Linux kernel did not properly verify the target namespace when handling
upcalls. An attacker could use this to expose sensitive information.
(CVE-2025-2312)
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:
- ARM32 architecture;
- ARM64 architecture;
- PowerPC architecture;
- x86 architecture;
- Compute Acceleration Framework;
- ACPI drivers;
- Ublk userspace block driver;
- Compressed RAM block device driver;
- Bus devices;
- AMD CDX bus driver;
- Clock framework and drivers;
- DM
Red Hat
kernel: keys: Fix UAF in key_put()
vendor_redhat·2025-03-31·CVSS 7.8
CVE-2025-21893 [HIGH] CWE-416 kernel: keys: Fix UAF in key_put()
kernel: keys: Fix UAF in key_put()
In the Linux kernel, the following vulnerability has been resolved:
keys: Fix UAF in key_put()
Once a key's reference count has been reduced to 0, the garbage collector
thread may destroy it at any time and so key_put() is not allowed to touch
the key after that point. The most key_put() is normally allowed to do is
to touch key_gc_work as that's a static global variable.
However, in an effort to speed up the reclamation of quota, this is now
done in key_put() once the key's usage is reduced to 0 - but now the code
is looking at the key after the deadline, which is forbidden.
Fix this by using a flag to indicate that a key can be gc'd now rather than
looking at the key's refcount in the garbage collector.
Package: kernel (Red Hat Enterprise Linux 6) - O
Debian
CVE-2025-21893: linux - In the Linux kernel, the following vulnerability has been resolved: keys: Fix U...
vendor_debian·2025·CVSS 7.8
CVE-2025-21893 [HIGH] CVE-2025-21893: linux - In the Linux kernel, the following vulnerability has been resolved: keys: Fix U...
In the Linux kernel, the following vulnerability has been resolved: keys: Fix UAF in key_put() Once a key's reference count has been reduced to 0, the garbage collector thread may destroy it at any time and so key_put() is not allowed to touch the key after that point. The most key_put() is normally allowed to do is to touch key_gc_work as that's a static global variable. However, in an effort to speed up the reclamation of quota, this is now done in key_put() once the key's usage is reduced to 0 - but now the code is looking at the key after the deadline, which is forbidden. Fix this by using a flag to indicate that a key can be gc'd now rather than looking at the key's refcount in the garbage collector.
Scope: local
bookworm: resolved
bullseye: resolved
forky: resolved (fixed in 6.12.21-
No detection rules found.
No public exploits indexed.
2025-03-31
Published