Linux: Double Free
CVE-2024-50055 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 d885c464c25018b81a6b58f5d548fc2e3ef87dd1, 9ce15f68abedfae7ae0a35e95895aeddfd0f0c6a, bfa54a793ba77ef696755b66f3ac4ed00c7d1248 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 0.25% 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 d885c464c25018b81a6b58f5d548fc2e3ef87dd1 or 9ce15f68abedfae7ae0a35e95895aeddfd0f0c6a or bfa54a793ba77ef696755b66f3ac4ed00c7d1248, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.4.291 or 5.10.231 or 5.15.174 or 6.1.120, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 3465e2e4a24eef9bc9f21aa29d83fd7000c1da48 up to, but not including, d885c464c25018b81a6b58f5d548fc2e3ef87dd1; 3465e2e4a24eef9bc9f21aa29d83fd7000c1da48 up to, but not including, 9ce15f68abedfae7ae0a35e95895aeddfd0f0c6a; 3465e2e4a24eef9bc9f21aa29d83fd7000c1da48 up to, but not including, bfa54a793ba77ef696755b66f3ac4ed00c7d1248; 6.3 | d885c464c25018b81a6b58f5d548fc2e3ef87dd1, 9ce15f68abedfae7ae0a35e95895aeddfd0f0c6a, bfa54a793ba77ef696755b66f3ac4ed00c7d1248 |
| Debian | Debian Linux | 11.0 | Not stated |
| Linux | Linux Kernel | before 5.4.291; 5.5 up to, but not including, 5.10.231; 5.11 up to, but not including, 5.15.174; 5.16 up to, but not including, 6.1.120; 6.2 up to, but not including, 6.6.57; 6.7 up to, but not including, 6.11.4 | 5.4.291, 5.10.231, 5.15.174, 6.1.120, 6.6.57, 6.11.4 |
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: driver core: bus: Fix double free in driver API bus_register() For bus_register(), any error which happens after kset_register() will cause that @priv are freed twice, fixed by setting @priv with NULL after the first 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: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Third-party and government advisories
- lists.debian.org/debian-lts-announce/2025/03/msg00001.htmlMailing List, Third Party Advisory
- lists.debian.org/debian-lts-announce/2025/03/msg00002.htmlMailing List, Third Party Advisory
Recent Double Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 9.8 Critical severity
- 7.5 High severity
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