smb: client: split cached_fid bitfields to avoid shared-byte RMW races (Linux Linux)

CVE-2026-23230
HIGH 8.8

At a glance

Source
NVD
EPSS
EPSS 0.28 % · percentile 20 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Modified

Description

In the Linux kernel, the following vulnerability has been resolved: smb: client: split cached_fid bitfields to avoid shared-byte RMW races is_open, has_lease and on_list are stored in the same bitfield byte in struct cached_fid but are updated in different code paths that may run concurrently. Bitfield assignments generate byte read–modify–write operations (e.g. `orb $mask, addr` on x86_64), so updating one flag can restore stale values of the others. A possible interleaving is: CPU1: load old byte (has_lease=1, on_list=1) CPU2: clear both flags (store 0) CPU1: RMW store (old | IS_OPEN) -> reintroduces cleared bits To avoid this class of races, convert these flags to separate bool fields.

Weaknesses (CWE)

  • CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization

References

Scores

VersionScoreVectorScored by
CVSS 3.1HIGH 8.8CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HLinux
CVSS 3.1HIGH 8.8CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)
CVSS 3.1MEDIUM 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HNVD · nvd@nist.gov (Primary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected ebe98f1447bbccf8228335c62d86af02a0ed23f7 < 569fecc56bfe4df66f05734d67daef887746656b ; affected ebe98f1447bbccf8228335c62d86af02a0ed23f7 < 4386f6af8aaedd0c5ad6f659b40cadcc8f423828 ; affected ebe98f1447bbccf8228335c62d86af02a0ed23f7 < 3eaa22d688311c708b73f3c68bc6d0c8e3f0f77a ; affected ebe98f1447bbccf8228335c62d86af02a0ed23f7 < c4b9edd55987384a1f201d3d07ff71e448d79c1b ; affected ebe98f1447bbccf8228335c62d86af02a0ed23f7 < 4cfa4c37dcbcfd70866e856200ed8a2894cac578 ; affected ebe98f1447bbccf8228335c62d86af02a0ed23f7 < ec306600d5ba7148c9dbf8f5a8f1f5c1a044a241
Linux · Linuxaffected 6.1 ; unaffected 0 < 6.1 ; unaffected 6.1.164 ≤ 6.1.* ; unaffected 6.6.125 ≤ 6.6.* ; unaffected 6.12.72 ≤ 6.12.* ; unaffected 6.18.11 ≤ 6.18.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD