Linux: Use After Free
CVE-2024-57798 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 f61b2e5e7821f868d6afc22382a66a30ee780ba0, 9735d40f5fde9970aa46e828ecc85c32571d58a2, ce55818b2d3a999f886af91679589e4644ff1dc8 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 0.22% 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 f61b2e5e7821f868d6afc22382a66a30ee780ba0 or 9735d40f5fde9970aa46e828ecc85c32571d58a2 or ce55818b2d3a999f886af91679589e4644ff1dc8 or e54b00086f7473dbda1a7d6fc47720ced157c6a8, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.1.123 or 6.6.69 or 6.12.8, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 9408cc94eb041d0c2f9f00189a613b94c0449450 up to, but not including, f61b2e5e7821f868d6afc22382a66a30ee780ba0; 9408cc94eb041d0c2f9f00189a613b94c0449450 up to, but not including, 9735d40f5fde9970aa46e828ecc85c32571d58a2; 9408cc94eb041d0c2f9f00189a613b94c0449450 up to, but not including, ce55818b2d3a999f886af91679589e4644ff1dc8; 9408cc94eb041d0c2f9f00189a613b94c0449450 up to, but not including, e54b00086f7473dbda1a7d6fc47720ced157c6a8; 5.5 | f61b2e5e7821f868d6afc22382a66a30ee780ba0, 9735d40f5fde9970aa46e828ecc85c32571d58a2, ce55818b2d3a999f886af91679589e4644ff1dc8, e54b00086f7473dbda1a7d6fc47720ced157c6a8 |
| Linux | Linux Kernel | before 6.1.123; 6.2 up to, but not including, 6.6.69; 6.7 up to, but not including, 6.12.8; 6.13 | 6.1.123, 6.6.69, 6.12.8 |
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/dp_mst: Ensure mst_primary pointer is valid in drm_dp_mst_handle_up_req() While receiving an MST up request message from one thread in drm_dp_mst_handle_up_req(), the MST topology could be removed from another thread via drm_dp_mst_topology_mgr_set_mst(false), freeing mst_primary and setting drm_dp_mst_topology_mgr::mst_primary to NULL. This could lead to a NULL deref/use-after-free of mst_primary in drm_dp_mst_handle_up_req(). Avoid the above by holding a reference for mst_primary in drm_dp_mst_handle_up_req() while it's used. v2: Fix kfreeing the request if getting an mst_primary reference fails.
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
Other references
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
- 9.8 Critical severity
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