Riskcovery

CVE-2025-37879

9p/net: fix improper handling of bogus negative read/write replies

State
Published
Severity
9.8 Critical
Published
May 9, 2025
Updated
Aug 5, 2026
Reserved
Apr 16, 2025

Read the record on cve.org

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)

Scores

CVSSScoreVectorSource
3.19.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HLinux

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb to before 468ff4a7c61fb811c596a7c44b6a5455e40fd12bAffected
  • 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb to before a68768e280b7d0c967ea509e791bb9b90adc94a5Affected
  • 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb to before c548f95688e2b5ae0e2ae43d53cf717156c7d034Affected
  • 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb to before 374e4cd75617c8c2552f562f39dd989583f5c330Affected
  • 070b3656cf228eaaef7b28b59264c5c7cdbdd0fb to before d0259a856afca31d699b706ed5e2adf11086c73bAffected
LinuxLinux
  • 4.1Affected
  • before 4.1Not affected
  • 6.1.136 through 6.1.*Not affected
  • 6.6.89 through 6.6.*Not affected
  • 6.12.26 through 6.12.*Not affected
  • 6.14.5 through 6.14.*Not affected
  • 6.15 and laterNot affected

References

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.