Linux: Use After Free
CVE-2024-42314 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 c1cc3326e27b0bd7a2806b40bc48e49afaf951e7, c205565e0f2f439f278a4a94ee97b67ef7b56ae8, b7859ff398b6b656e1689daa860eb34837b4bb89 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 0.23% 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 c1cc3326e27b0bd7a2806b40bc48e49afaf951e7 or c205565e0f2f439f278a4a94ee97b67ef7b56ae8 or b7859ff398b6b656e1689daa860eb34837b4bb89 or 8e7860543a94784d744c7ce34b78a2e11beefa5c, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.1.108 or 6.6.44 or 6.10.3, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 6a4049102055250256623ab1875fabd89004bff8 up to, but not including, c1cc3326e27b0bd7a2806b40bc48e49afaf951e7; 6a4049102055250256623ab1875fabd89004bff8 up to, but not including, c205565e0f2f439f278a4a94ee97b67ef7b56ae8; 6a4049102055250256623ab1875fabd89004bff8 up to, but not including, b7859ff398b6b656e1689daa860eb34837b4bb89; 6a4049102055250256623ab1875fabd89004bff8 up to, but not including, 8e7860543a94784d744c7ce34b78a2e11beefa5c; 5.16 | c1cc3326e27b0bd7a2806b40bc48e49afaf951e7, c205565e0f2f439f278a4a94ee97b67ef7b56ae8, b7859ff398b6b656e1689daa860eb34837b4bb89, 8e7860543a94784d744c7ce34b78a2e11beefa5c |
| Debian | Debian Linux | 11.0 | Not stated |
| Linux | Linux Kernel | 5.16 up to, but not including, 6.1.108; 6.2 up to, but not including, 6.6.44; 6.7 up to, but not including, 6.10.3 | 6.1.108, 6.6.44, 6.10.3 |
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 | CNA |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix extent map use-after-free when adding pages to compressed bio At add_ra_bio_pages() we are accessing the extent map to calculate 'add_size' after we dropped our reference on the extent map, resulting in a use-after-free. Fix this by computing 'add_size' before dropping our extent map reference.
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
Third-party and government advisories
- lists.debian.org/debian-lts-announce/2025/01/msg00001.htmlMailing List, Third Party Advisory
Recent Use After Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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