Linux: Use After Free
CVE-2026-53296 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 0ad8c4a03a358de7811ba1ab8cbd1fe76ad0ff6b, 15c4cc3850cfe1b973eb7b63c02314b267f06a64, 187069ccc3474516af32350e20d7e449160fa6de 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 0.18% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 0ad8c4a03a358de7811ba1ab8cbd1fe76ad0ff6b or 15c4cc3850cfe1b973eb7b63c02314b267f06a64 or 187069ccc3474516af32350e20d7e449160fa6de or 81c9e7e4030e71391ab479c4c6e17b64802577aa, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.10.258 or 5.15.209 or 6.1.175 or 6.6.141, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 8ea4484d0c2bb4e2152261943fa1a3522654b1c7 up to, but not including, 0ad8c4a03a358de7811ba1ab8cbd1fe76ad0ff6b; 8ea4484d0c2bb4e2152261943fa1a3522654b1c7 up to, but not including, 15c4cc3850cfe1b973eb7b63c02314b267f06a64; 8ea4484d0c2bb4e2152261943fa1a3522654b1c7 up to, but not including, 187069ccc3474516af32350e20d7e449160fa6de; 8ea4484d0c2bb4e2152261943fa1a3522654b1c7 up to, but not including, 81c9e7e4030e71391ab479c4c6e17b64802577aa; 8ea4484d0c2bb4e2152261943fa1a3522654b1c7 up to, but not including, 6c6ce2ccb4fcf1617fec83f91b21aa0265f30701; 8ea4484d0c2bb4e2152261943fa1a3522654b1c7 up to, but not including, 742001919653e7313b4e91780c5d108be1692365; 8ea4484d0c2bb4e2152261943fa1a3522654b1c7 up to, but not including, 02beb178e2e159daeb8f992d7abb16a37da31664; 8ea4484d0c2bb4e2152261943fa1a3522654b1c7 up to, but not including, c02053a9055d5fdfd32432287cca8958db1d5bc5; and 1 more ranges | 0ad8c4a03a358de7811ba1ab8cbd1fe76ad0ff6b, 15c4cc3850cfe1b973eb7b63c02314b267f06a64, 187069ccc3474516af32350e20d7e449160fa6de, 81c9e7e4030e71391ab479c4c6e17b64802577aa, 6c6ce2ccb4fcf1617fec83f91b21aa0265f30701, 742001919653e7313b4e91780c5d108be1692365 |
| Linux | Linux Kernel | 4.4 up to, but not including, 5.10.258; 5.11 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; 7.1 | 5.10.258, 5.15.209, 6.1.175, 6.6.141, 6.12.91, 6.18.33 |
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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- 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:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
Official description
In the Linux kernel, the following vulnerability has been resolved: mailbox: mailbox-test: free channels on probe error On probe error, free the previously obtained channels. This not only prevents a leak, but also UAF scenarios because the client structure will be removed nonetheless because it was allocated with devm.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/02beb178e2e159daeb8f992d7abb16a37da31664
- git.kernel.org/stable/c/0ad8c4a03a358de7811ba1ab8cbd1fe76ad0ff6b
- git.kernel.org/stable/c/15c4cc3850cfe1b973eb7b63c02314b267f06a64
- git.kernel.org/stable/c/187069ccc3474516af32350e20d7e449160fa6de
- git.kernel.org/stable/c/6c6ce2ccb4fcf1617fec83f91b21aa0265f30701
- git.kernel.org/stable/c/742001919653e7313b4e91780c5d108be1692365
- git.kernel.org/stable/c/81c9e7e4030e71391ab479c4c6e17b64802577aa
- git.kernel.org/stable/c/c02053a9055d5fdfd32432287cca8958db1d5bc5
Recent Use After Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.5 High severity
- 9.8 Critical severity
- 7.8 High severity
- 7.8 High severity
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