Linux: Double Free
CVE-2025-38411 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 d18facba5a5795ad44b2a00a052e3db2fa77ab12, 9df7b5ebead649b00bf9a53a798e4bf83a1318fd, 6.15.6 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 0.38% 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 d18facba5a5795ad44b2a00a052e3db2fa77ab12 or 9df7b5ebead649b00bf9a53a798e4bf83a1318fd or 6.15.6, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.15.6 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 329ba1cb402ac328224965b8fc7a554a5150908e up to, but not including, d18facba5a5795ad44b2a00a052e3db2fa77ab12; 2b1424cd131cfaba4cf7040473133d26cddac088 up to, but not including, 9df7b5ebead649b00bf9a53a798e4bf83a1318fd; 6.15.3 up to, but not including, 6.15.6 | d18facba5a5795ad44b2a00a052e3db2fa77ab12, 9df7b5ebead649b00bf9a53a798e4bf83a1318fd, 6.15.6 |
| Linux | Linux Kernel | 6.15.3 up to, but not including, 6.15.6; 6.16 | 6.15.6 |
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 | 9.8 | Critical | CNA |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: netfs: Fix double put of request If a netfs request finishes during the pause loop, it will have the ref that belongs to the IN_PROGRESS flag removed at that point - however, if it then goes to the final wait loop, that will *also* put the ref because it sees that the IN_PROGRESS flag is clear and incorrectly assumes that this happened when it called the collector. In fact, since IN_PROGRESS is clear, we shouldn't call the collector again since it's done all the cleanup, such as calling ->ki_complete(). Fix this by making netfs_collect_in_app() just return, indicating that we're done if IN_PROGRESS is removed.
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.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Recent Double Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 8.2 High severity
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