CVE-2025-21911
MediumIn the Linux kernel, the following vulnerability has been resolved: drm/imagination: avoid deadlock on fence release Do scheduler queue fence release processing on a workqueue, rather than in the release function itself. Fixes deadlock issues such as the following: [ 607.400437] ============================================ [ 607.405755] WARNING: possible recursive locking detected [ 607.415500] -------------------------------------------- [ 607.420817] weston:zfq0/24149 is trying to acquire lock: [ 607.426131] ffff000017d041a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: pvr_gem_object_vunmap+0x40/0xc0 [powervr] [ 607.436728] but task is already holding lock: [ 607.442554] ffff000017d105a0 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_ioctl+0x250/0x554 [ 607.451727] other info that might help us debug this: [ 607.458245] Possible unsafe locking scenario: [ 607.464155] CPU0 [ 607.466601] ---- [ 607.469044] lock(reservation_ww_class_mutex); [ 607.473584] lock(reservation_ww_class_mutex); [ 607.478114] *** DEADLOCK ***
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-667CVE-2025-21911 is a Improper Locking vulnerability
What is Improper Locking?
The product does not properly acquire or release a lock, which can lead to unexpected behaviour. Learn more on MITRE CWE
Affected versions
Linux kernel versions
6.8
and later are affected. Fixed in
6.12.19,
6.13.7,
6.14
and their respective stable series.
References
The following references provide additional information about CVE-2025-21911 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/9bd8b8d34cf4efba18766d64f817c819ed1bbde7
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PatchKernel patch commithttps://git.kernel.org/stable/c/d993ae7360923efd6ade43a32043459a121c28c1
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PatchKernel patch commithttps://git.kernel.org/stable/c/df1a1ed5e1bdd9cc13148e0e5549f5ebcf76cf13
Frequently asked questions
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What is CVE-2025-21911?
CVE-2025-21911 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as an Improper Locking flaw (CWE-667) . It affects Linux kernel versions from 6.8 onward and has been patched in 6.12.19, 6.13.7 and 6.14. CVE-2025-21911 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2025-21911?
CVE-2025-21911 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2025-21911?
Yes — CVE-2025-21911 has been patched. Fixed versions include 6.12.19, 6.13.7 and 6.14. If you are running Linux kernel 6.8 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2025-21911 actively exploited?
No — CVE-2025-21911 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Improper Locking (CWE-667)?
The product does not properly acquire or release a lock, which can lead to unexpected behaviour. View CWE-667 on MITRE CWE →