Linux: Double Free
CVE-2024-50235 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 ba392e1355ba74b1d4fa11b85f71ab6ed7ecc058, 6c44abb2d4c3262737d5d67832daebc8cf48b8c9, 64e4c45d23cd7f6167f69cc2d2877bc7f54292e5 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 ba392e1355ba74b1d4fa11b85f71ab6ed7ecc058 or 6c44abb2d4c3262737d5d67832daebc8cf48b8c9 or 64e4c45d23cd7f6167f69cc2d2877bc7f54292e5 or d5fee261dfd9e17b08b1df8471ac5d5736070917, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.1.116 or 6.6 or 6.6.60 or 6.11.7, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | c797498e860e9a435a651bbf0789433684ce6dd8 up to, but not including, ba392e1355ba74b1d4fa11b85f71ab6ed7ecc058; 37c20b2effe987b806c8de6d12978e4ffeff026f up to, but not including, 6c44abb2d4c3262737d5d67832daebc8cf48b8c9; 37c20b2effe987b806c8de6d12978e4ffeff026f up to, but not including, 64e4c45d23cd7f6167f69cc2d2877bc7f54292e5; 37c20b2effe987b806c8de6d12978e4ffeff026f up to, but not including, d5fee261dfd9e17b08b1df8471ac5d5736070917; 32fb9b7d98c3e586bddfb978d383aa8d2b1211bc; 6.1.57 up to, but not including, 6.1.116; 6.5.7 up to, but not including, 6.6; 6.6 | ba392e1355ba74b1d4fa11b85f71ab6ed7ecc058, 6c44abb2d4c3262737d5d67832daebc8cf48b8c9, 64e4c45d23cd7f6167f69cc2d2877bc7f54292e5, d5fee261dfd9e17b08b1df8471ac5d5736070917, 6.1.116, 6.6 |
| Linux | Linux Kernel | 6.1.57 up to, but not including, 6.1.116; 6.5.7 up to, but not including, 6.6; 6.6 up to, but not including, 6.6.60; 6.7 up to, but not including, 6.11.7; 6.12 | 6.1.116, 6.6, 6.6.60, 6.11.7 |
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: wifi: cfg80211: clear wdev->cqm_config pointer on free When we free wdev->cqm_config when unregistering, we also need to clear out the pointer since the same wdev/netdev may get re-registered in another network namespace, then destroyed later, running this code again, which results in a double-free.
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: total).
- 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
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.4 High severity
- 7.8 High severity
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