Linux: Use After Free
CVE-2023-53316 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 c67a55f7cc8d767d624235bf1bcd0947e56abe0f, 3c3f3d35f5e05c468b048eb42a4f8c62c6655692, 4e9f1a2367aea7d61f6781213e25313cd983b0d7 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 0.16% 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 c67a55f7cc8d767d624235bf1bcd0947e56abe0f or 3c3f3d35f5e05c468b048eb42a4f8c62c6655692 or 4e9f1a2367aea7d61f6781213e25313cd983b0d7 or 5c3278db06e332fdc14f3f297499fb88ded264d2, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.10.188 or 5.15.121 or 6.1.39 or 6.3.13, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | c943b4948b5848fc0e07f875edbd35a973879e22 up to, but not including, c67a55f7cc8d767d624235bf1bcd0947e56abe0f; c943b4948b5848fc0e07f875edbd35a973879e22 up to, but not including, 3c3f3d35f5e05c468b048eb42a4f8c62c6655692; c943b4948b5848fc0e07f875edbd35a973879e22 up to, but not including, 4e9f1a2367aea7d61f6781213e25313cd983b0d7; c943b4948b5848fc0e07f875edbd35a973879e22 up to, but not including, 5c3278db06e332fdc14f3f297499fb88ded264d2; c943b4948b5848fc0e07f875edbd35a973879e22 up to, but not including, ca47d0dc00968358c136a1847cfed550cedfd1b5; c943b4948b5848fc0e07f875edbd35a973879e22 up to, but not including, fa0048a4b1fa7a50c8b0e514f5b428abdf69a6f8; 5.10 | c67a55f7cc8d767d624235bf1bcd0947e56abe0f, 3c3f3d35f5e05c468b048eb42a4f8c62c6655692, 4e9f1a2367aea7d61f6781213e25313cd983b0d7, 5c3278db06e332fdc14f3f297499fb88ded264d2, ca47d0dc00968358c136a1847cfed550cedfd1b5, fa0048a4b1fa7a50c8b0e514f5b428abdf69a6f8 |
| Linux | Linux Kernel | 5.10 up to, but not including, 5.10.188; 5.11 up to, but not including, 5.15.121; 5.16 up to, but not including, 6.1.39; 6.2 up to, but not including, 6.3.13; 6.4 up to, but not including, 6.4.4 | 5.10.188, 5.15.121, 6.1.39, 6.3.13, 6.4.4 |
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.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | NVD |
| CVSS 3.1 | 7.8 | High | CISA (ADP) |
Official description
In the Linux kernel, the following vulnerability has been resolved: drm/msm/dp: Free resources after unregistering them The DP component's unbind operation walks through the submodules to unregister and clean things up. But if the unbind happens because the DP controller itself is being removed, all the memory for those submodules has just been freed. Change the order of these operations to avoid the many use-after-free that otherwise happens in this code path. Patchwork: https://patchwork.freedesktop.org/patch/542166/
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: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/3c3f3d35f5e05c468b048eb42a4f8c62c6655692
- git.kernel.org/stable/c/4e9f1a2367aea7d61f6781213e25313cd983b0d7
- git.kernel.org/stable/c/5c3278db06e332fdc14f3f297499fb88ded264d2
- git.kernel.org/stable/c/c67a55f7cc8d767d624235bf1bcd0947e56abe0f
- git.kernel.org/stable/c/ca47d0dc00968358c136a1847cfed550cedfd1b5
- git.kernel.org/stable/c/fa0048a4b1fa7a50c8b0e514f5b428abdf69a6f8
Recent Use After Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.0 High severity
- 7.8 High severity
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