Linux: Use After Free
CVE-2023-52600 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 81b4249ef37297fb17ba102a524039a05c6c5d35, 93df0a2a0b3cde2d7ab3a52ed46ea1d6d4aaba5f, bc6ef64dbe71136f327d63b2b9071b828af2c2a8 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 0.28% 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 81b4249ef37297fb17ba102a524039a05c6c5d35 or 93df0a2a0b3cde2d7ab3a52ed46ea1d6d4aaba5f or bc6ef64dbe71136f327d63b2b9071b828af2c2a8 or 8e44dc3f96e903815dab1d74fff8faafdc6feb61, whichever matches your release line, or a later version.
- Update Linux Kernel to 4.19.307 or 5.4.269 or 5.10.210 or 5.15.149, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 81b4249ef37297fb17ba102a524039a05c6c5d35; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 93df0a2a0b3cde2d7ab3a52ed46ea1d6d4aaba5f; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, bc6ef64dbe71136f327d63b2b9071b828af2c2a8; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 8e44dc3f96e903815dab1d74fff8faafdc6feb61; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 32e8f2d95528d45828c613417cb2827d866cbdce; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 1696d6d7d4a1b373e96428d0fe1166bd7c3c795e; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, bacdaa04251382d7efd4f09f9a0686bfcc297e2e; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, e0e1958f4c365e380b17ccb35617345b31ef7bf3; and 1 more ranges | 81b4249ef37297fb17ba102a524039a05c6c5d35, 93df0a2a0b3cde2d7ab3a52ed46ea1d6d4aaba5f, bc6ef64dbe71136f327d63b2b9071b828af2c2a8, 8e44dc3f96e903815dab1d74fff8faafdc6feb61, 32e8f2d95528d45828c613417cb2827d866cbdce, 1696d6d7d4a1b373e96428d0fe1166bd7c3c795e |
| Linux | Linux Kernel | before 4.19.307; 4.20 up to, but not including, 5.4.269; 5.5 up to, but not including, 5.10.210; 5.11 up to, but not including, 5.15.149; 5.16 up to, but not including, 6.1.77; 6.2 up to, but not including, 6.6.16; 6.7 up to, but not including, 6.7.4 | 4.19.307, 5.4.269, 5.10.210, 5.15.149, 6.1.77, 6.6.16 |
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: jfs: fix uaf in jfs_evict_inode When the execution of diMount(ipimap) fails, the object ipimap that has been released may be accessed in diFreeSpecial(). Asynchronous ipimap release occurs when rcu_core() calls jfs_free_node(). Therefore, when diMount(ipimap) fails, sbi->ipimap should not be initialized as ipimap.
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/1696d6d7d4a1b373e96428d0fe1166bd7c3c795e
- git.kernel.org/stable/c/32e8f2d95528d45828c613417cb2827d866cbdce
- git.kernel.org/stable/c/81b4249ef37297fb17ba102a524039a05c6c5d35
- git.kernel.org/stable/c/8e44dc3f96e903815dab1d74fff8faafdc6feb61
- git.kernel.org/stable/c/93df0a2a0b3cde2d7ab3a52ed46ea1d6d4aaba5f
- git.kernel.org/stable/c/bacdaa04251382d7efd4f09f9a0686bfcc297e2e
- git.kernel.org/stable/c/bc6ef64dbe71136f327d63b2b9071b828af2c2a8
- git.kernel.org/stable/c/e0e1958f4c365e380b17ccb35617345b31ef7bf3
- lists.debian.org/debian-lts-announce/2024/06/msg00017.html
- lists.debian.org/debian-lts-announce/2024/06/msg00020.html
Recent Use After Free vulnerabilities
- 9.1 Critical severity
- 8.8 High severity
- 9.8 Critical severity
- 7.8 High severity
- 7.1 High severity
- 7.8 High severity
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