Linux: Out-of-bounds Read
CVE-2025-37879 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.1 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 468ff4a7c61fb811c596a7c44b6a5455e40fd12b, a68768e280b7d0c967ea509e791bb9b90adc94a5, c548f95688e2b5ae0e2ae43d53cf717156c7d034 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 0.73% chance of exploitation within 30 days, higher than 55% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 468ff4a7c61fb811c596a7c44b6a5455e40fd12b or a68768e280b7d0c967ea509e791bb9b90adc94a5 or c548f95688e2b5ae0e2ae43d53cf717156c7d034 or 374e4cd75617c8c2552f562f39dd989583f5c330, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.1.136 or 6.6.89 or 6.12.26 or 6.14.5, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb up to, but not including, 468ff4a7c61fb811c596a7c44b6a5455e40fd12b; 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb up to, but not including, a68768e280b7d0c967ea509e791bb9b90adc94a5; 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb up to, but not including, c548f95688e2b5ae0e2ae43d53cf717156c7d034; 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb up to, but not including, 374e4cd75617c8c2552f562f39dd989583f5c330; 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb up to, but not including, d0259a856afca31d699b706ed5e2adf11086c73b; 4.1 | 468ff4a7c61fb811c596a7c44b6a5455e40fd12b, a68768e280b7d0c967ea509e791bb9b90adc94a5, c548f95688e2b5ae0e2ae43d53cf717156c7d034, 374e4cd75617c8c2552f562f39dd989583f5c330, d0259a856afca31d699b706ed5e2adf11086c73b |
| Linux | Linux Kernel | before 6.1.136; 6.2 up to, but not including, 6.6.89; 6.7 up to, but not including, 6.12.26; 6.13 up to, but not including, 6.14.5 | 6.1.136, 6.6.89, 6.12.26, 6.14.5 |
| Debian | Debian Linux | 11.0 | Not stated |
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
- NoneNothing can be modified.
- 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:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.8 | Critical | CNA |
| CVSS 3.1 | 7.1 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: 9p/net: fix improper handling of bogus negative read/write replies In p9_client_write() and p9_client_read_once(), if the server incorrectly replies with success but a negative write/read count then we would consider written (negative) <= rsize (positive) because both variables were signed. Make variables unsigned to avoid this problem. The reproducer linked below now fails with the following error instead of a null pointer deref: 9pnet: bogus RWRITE count (4294967295 > 3)
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/374e4cd75617c8c2552f562f39dd989583f5c330
- git.kernel.org/stable/c/468ff4a7c61fb811c596a7c44b6a5455e40fd12b
- git.kernel.org/stable/c/a68768e280b7d0c967ea509e791bb9b90adc94a5
- git.kernel.org/stable/c/c548f95688e2b5ae0e2ae43d53cf717156c7d034
- git.kernel.org/stable/c/d0259a856afca31d699b706ed5e2adf11086c73b
Third-party and government advisories
- lists.debian.org/debian-lts-announce/2025/05/msg00045.htmlMailing List, Third Party Advisory
Recent Out-of-bounds Read vulnerabilities
- 7.1 High severity
- 8.4 High severity
- 7.1 High severity
- 7.5 High severity
- 7.8 High severity
- 7.1 High severity
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