Linux: Use After Free
CVE-2024-26872 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.0 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 bdd895e0190c464f54f84579e7535d80276f0fc5, 6413e78086caf7bf15639923740da0d91fdfd090, e362d007294955a4fb929e1c8978154a64efdcb6 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 0.24% 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 bdd895e0190c464f54f84579e7535d80276f0fc5 or 6413e78086caf7bf15639923740da0d91fdfd090 or e362d007294955a4fb929e1c8978154a64efdcb6 or 85570b91e4820a0db9d9432098778cafafa7d217, whichever matches your release line, or a later version.
- Update SIMATIC S7-1500 TM MFP - GNU/Linux subsystem to V1.1.1 or a later version.
- Update Linux Kernel to 5.10.214 or 5.15.153 or 6.1.83 or 6.6.23, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | a42d985bd5b234da8b61347a78dc3057bf7bb94d up to, but not including, bdd895e0190c464f54f84579e7535d80276f0fc5; a42d985bd5b234da8b61347a78dc3057bf7bb94d up to, but not including, 6413e78086caf7bf15639923740da0d91fdfd090; a42d985bd5b234da8b61347a78dc3057bf7bb94d up to, but not including, e362d007294955a4fb929e1c8978154a64efdcb6; a42d985bd5b234da8b61347a78dc3057bf7bb94d up to, but not including, 85570b91e4820a0db9d9432098778cafafa7d217; a42d985bd5b234da8b61347a78dc3057bf7bb94d up to, but not including, 7104a00fa37ae898a827381f1161fa3286c8b346; a42d985bd5b234da8b61347a78dc3057bf7bb94d up to, but not including, ec77fa12da41260c6bf9e060b89234b980c5130f; a42d985bd5b234da8b61347a78dc3057bf7bb94d up to, but not including, c21a8870c98611e8f892511825c9607f1e2cd456; 3.3 | bdd895e0190c464f54f84579e7535d80276f0fc5, 6413e78086caf7bf15639923740da0d91fdfd090, e362d007294955a4fb929e1c8978154a64efdcb6, 85570b91e4820a0db9d9432098778cafafa7d217, 7104a00fa37ae898a827381f1161fa3286c8b346, ec77fa12da41260c6bf9e060b89234b980c5130f |
| Siemens | SIMATIC S7-1500 TM MFP - GNU/Linux subsystem | before V1.1.1 | V1.1.1 |
| Linux | Linux Kernel | 3.3 up to, but not including, 5.10.214; 5.11 up to, but not including, 5.15.153; 5.16 up to, but not including, 6.1.83; 6.2 up to, but not including, 6.6.23; 6.7 up to, but not including, 6.7.11; 6.8 up to, but not including, 6.8.2 | 5.10.214, 5.15.153, 6.1.83, 6.6.23, 6.7.11, 6.8.2 |
| Debian | Debian Linux | 10.0 | Not stated |
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
- HighSuccess depends on conditions outside the attacker's control.
- 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:H/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 | 7.0 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: RDMA/srpt: Do not register event handler until srpt device is fully setup Upon rare occasions, KASAN reports a use-after-free Write in srpt_refresh_port(). This seems to be because an event handler is registered before the srpt device is fully setup and a race condition upon error may leave a partially setup event handler in place. Instead, only register the event handler after srpt device initialization is complete.
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/6413e78086caf7bf15639923740da0d91fdfd090Mailing List
- git.kernel.org/stable/c/7104a00fa37ae898a827381f1161fa3286c8b346Mailing List
- git.kernel.org/stable/c/85570b91e4820a0db9d9432098778cafafa7d217Mailing List
- git.kernel.org/stable/c/bdd895e0190c464f54f84579e7535d80276f0fc5Mailing List
- git.kernel.org/stable/c/c21a8870c98611e8f892511825c9607f1e2cd456Mailing List
- git.kernel.org/stable/c/e362d007294955a4fb929e1c8978154a64efdcb6Mailing List
- git.kernel.org/stable/c/ec77fa12da41260c6bf9e060b89234b980c5130fMailing List
Other references
Recent Use After Free vulnerabilities
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