Linux: Double Free
CVE-2024-36973 is a high-severity double 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 34ae447b138680b5ed3660f7d935ff3faf88ba1a, 86c9713602f786f441630c4ee02891987f8618b9, 1efe551982297924d05a367aa2b6ec3d275d5742 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 34ae447b138680b5ed3660f7d935ff3faf88ba1a or 86c9713602f786f441630c4ee02891987f8618b9 or 1efe551982297924d05a367aa2b6ec3d275d5742 or 086c6cbcc563c81d55257f9b27e14faf1d0963d3, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.1.95 or 6.6.35 or 6.9.6, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 393fc2f5948fd340d016a9557eea6e1ac2f6c60c up to, but not including, 34ae447b138680b5ed3660f7d935ff3faf88ba1a; 393fc2f5948fd340d016a9557eea6e1ac2f6c60c up to, but not including, 86c9713602f786f441630c4ee02891987f8618b9; 393fc2f5948fd340d016a9557eea6e1ac2f6c60c up to, but not including, 1efe551982297924d05a367aa2b6ec3d275d5742; 393fc2f5948fd340d016a9557eea6e1ac2f6c60c up to, but not including, 086c6cbcc563c81d55257f9b27e14faf1d0963d3; 6.1 | 34ae447b138680b5ed3660f7d935ff3faf88ba1a, 86c9713602f786f441630c4ee02891987f8618b9, 1efe551982297924d05a367aa2b6ec3d275d5742, 086c6cbcc563c81d55257f9b27e14faf1d0963d3 |
| Linux | Linux Kernel | 6.1 up to, but not including, 6.1.95; 6.2 up to, but not including, 6.6.35; 6.7 up to, but not including, 6.9.6; 6.10 | 6.1.95, 6.6.35, 6.9.6 |
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 | 8.4 | High | CNA |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: misc: microchip: pci1xxxx: fix double free in the error handling of gp_aux_bus_probe() When auxiliary_device_add() returns error and then calls auxiliary_device_uninit(), callback function gp_auxiliary_device_release() calls ida_free() and kfree(aux_device_wrapper) to free memory. We should't call them again in the error handling path. Fix this by skipping the redundant cleanup functions.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Double Free
The product calls free() twice on the same memory address.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
- Use a static analysis tool to find double free instances.
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
Other references
Recent Double Free vulnerabilities
- 7.8 High severity
- 7.1 High severity
- 8.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
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