Linux: Improper Locking
CVE-2026-53049 is a critical-severity improper locking vulnerability in Linux, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 3b28eb75afe520972bacc833850c2b30aa0824cd, ca95342cb1b39062a03c115830286f0a426053d5, bf5fcd9c37c2546beaf7b401d31aefd89017dc3d as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.39% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Linux to 3b28eb75afe520972bacc833850c2b30aa0824cd or ca95342cb1b39062a03c115830286f0a426053d5 or bf5fcd9c37c2546beaf7b401d31aefd89017dc3d or f2f225cf505ac016132ded21690f3ba0a080a4e8, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.15.209 or 6.1.175 or 6.6.141 or 6.12.91, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 5e4c7632aae1cce137792647f4fb6f599d1da893 up to, but not including, 3b28eb75afe520972bacc833850c2b30aa0824cd; 5e4c7632aae1cce137792647f4fb6f599d1da893 up to, but not including, ca95342cb1b39062a03c115830286f0a426053d5; 5e4c7632aae1cce137792647f4fb6f599d1da893 up to, but not including, bf5fcd9c37c2546beaf7b401d31aefd89017dc3d; 5e4c7632aae1cce137792647f4fb6f599d1da893 up to, but not including, f2f225cf505ac016132ded21690f3ba0a080a4e8; 5e4c7632aae1cce137792647f4fb6f599d1da893 up to, but not including, 49d9be0722da3a4a893ba905720cba1921834ec3; 5e4c7632aae1cce137792647f4fb6f599d1da893 up to, but not including, 98e8bf249c790d56de1abc4a5f8bd68035a00921; 5e4c7632aae1cce137792647f4fb6f599d1da893 up to, but not including, fe2c8d051150b90b3ccb85f89e3b1d636cb88ec8; 5.7 | 3b28eb75afe520972bacc833850c2b30aa0824cd, ca95342cb1b39062a03c115830286f0a426053d5, bf5fcd9c37c2546beaf7b401d31aefd89017dc3d, f2f225cf505ac016132ded21690f3ba0a080a4e8, 49d9be0722da3a4a893ba905720cba1921834ec3, 98e8bf249c790d56de1abc4a5f8bd68035a00921 |
| Linux | Linux Kernel | 5.7 up to, but not including, 5.15.209; 5.16 up to, but not including, 6.1.175; 6.2 up to, but not including, 6.6.141; 6.7 up to, but not including, 6.12.91; 6.13 up to, but not including, 6.18.33; 6.19 up to, but not including, 7.0.10 | 5.15.209, 6.1.175, 6.6.141, 6.12.91, 6.18.33, 7.0.10 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: gfs2: add some missing log locking Function gfs2_logd() calls the log flushing functions gfs2_ail1_start(), gfs2_ail1_wait(), and gfs2_ail1_empty() without holding sdp->sd_log_flush_lock, but these functions require exclusion against concurrent transactions. To fix that, add a non-locking __gfs2_log_flush() function. Then, in gfs2_logd(), take sdp->sd_log_flush_lock before calling the above mentioned log flushing functions and __gfs2_log_flush().
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Locking
The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.
How developers prevent this class of flaw
- Use industry standard APIs to implement locking mechanism.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/3b28eb75afe520972bacc833850c2b30aa0824cd
- git.kernel.org/stable/c/49d9be0722da3a4a893ba905720cba1921834ec3
- git.kernel.org/stable/c/98e8bf249c790d56de1abc4a5f8bd68035a00921
- git.kernel.org/stable/c/bf5fcd9c37c2546beaf7b401d31aefd89017dc3d
- git.kernel.org/stable/c/ca95342cb1b39062a03c115830286f0a426053d5
- git.kernel.org/stable/c/f2f225cf505ac016132ded21690f3ba0a080a4e8
- git.kernel.org/stable/c/fe2c8d051150b90b3ccb85f89e3b1d636cb88ec8
Recent Improper Locking vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.5 High severity
- 7.5 High severity
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