Linux: Use After Free
CVE-2024-26598 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 d04acadb6490aa3314f9c9e087691e55de153b88, ba7be666740847d967822bed15500656b26bc703, 12c2759ab1343c124ed46ba48f27bd1ef5d2dff4 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 d04acadb6490aa3314f9c9e087691e55de153b88 or ba7be666740847d967822bed15500656b26bc703 or 12c2759ab1343c124ed46ba48f27bd1ef5d2dff4 or dba788e25f05209adf2b0175eb1691dc89fb1ba6, whichever matches your release line, or a later version.
- Update linux_kernel to d04acadb6490 or ba7be6667408 or 12c2759ab134 or dba788e25f05, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 6211753fdfd05af9e08f54c8d0ba3ee516034878 up to, but not including, d04acadb6490aa3314f9c9e087691e55de153b88; 6211753fdfd05af9e08f54c8d0ba3ee516034878 up to, but not including, ba7be666740847d967822bed15500656b26bc703; 6211753fdfd05af9e08f54c8d0ba3ee516034878 up to, but not including, 12c2759ab1343c124ed46ba48f27bd1ef5d2dff4; 6211753fdfd05af9e08f54c8d0ba3ee516034878 up to, but not including, dba788e25f05209adf2b0175eb1691dc89fb1ba6; 6211753fdfd05af9e08f54c8d0ba3ee516034878 up to, but not including, 65b201bf3e9af1b0254243a5881390eda56f72d1; 6211753fdfd05af9e08f54c8d0ba3ee516034878 up to, but not including, dd3956a1b3dd11f46488c928cb890d6937d1ca80; 6211753fdfd05af9e08f54c8d0ba3ee516034878 up to, but not including, ad362fe07fecf0aba839ff2cc59a3617bd42c33f; 3.11 | d04acadb6490aa3314f9c9e087691e55de153b88, ba7be666740847d967822bed15500656b26bc703, 12c2759ab1343c124ed46ba48f27bd1ef5d2dff4, dba788e25f05209adf2b0175eb1691dc89fb1ba6, 65b201bf3e9af1b0254243a5881390eda56f72d1, dd3956a1b3dd11f46488c928cb890d6937d1ca80 |
| Linux | linux_kernel | 1da177e4c3f4 up to, but not including, d04acadb6490; 1da177e4c3f4 up to, but not including, ba7be6667408; 1da177e4c3f4 up to, but not including, 12c2759ab134; 1da177e4c3f4 up to, but not including, dba788e25f05; 1da177e4c3f4 up to, but not including, 65b201bf3e9a; 1da177e4c3f4 up to, but not including, dd3956a1b3dd; 1da177e4c3f4 up to, but not including, ad362fe07fec | d04acadb6490, ba7be6667408, 12c2759ab134, dba788e25f05, 65b201bf3e9a, dd3956a1b3dd |
| 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
- 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 | 8.8 | High | CNA |
| 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: KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache There is a potential UAF scenario in the case of an LPI translation cache hit racing with an operation that invalidates the cache, such as a DISCARD ITS command. The root of the problem is that vgic_its_check_cache() does not elevate the refcount on the vgic_irq before dropping the lock that serializes refcount changes. Have vgic_its_check_cache() raise the refcount on the returned vgic_irq and add the corresponding decrement after queueing the interrupt.
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/12c2759ab1343c124ed46ba48f27bd1ef5d2dff4
- git.kernel.org/stable/c/65b201bf3e9af1b0254243a5881390eda56f72d1
- git.kernel.org/stable/c/ad362fe07fecf0aba839ff2cc59a3617bd42c33f
- git.kernel.org/stable/c/ba7be666740847d967822bed15500656b26bc703
- git.kernel.org/stable/c/d04acadb6490aa3314f9c9e087691e55de153b88
- git.kernel.org/stable/c/dba788e25f05209adf2b0175eb1691dc89fb1ba6
- git.kernel.org/stable/c/dd3956a1b3dd11f46488c928cb890d6937d1ca80
Other references
Recent Use After Free vulnerabilities
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