High [CVE-2026-64379] mask server-provided mode to 07777 in modefromsid
This high-severity Red Hat Linux advisory covers CVE-2026-64379 affecting Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9.
Aggregated and source-linked by VulniPulse. Data sources, validation and limitations.
VulniPulse record published Record updated
Android app · Google Play
Monitor future Red Hat Linux CVEs from your phone.
Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: client: mask server-provided mode to 07777 in modefromsid When modefromsid is active, parse_dacl() applies the server-provided sub_auth[2] value from the NFS mode SID to cf_mode without masking to 07777. Apply the correct masking, same as in the read path.
When processing server-provided file mode information, the system incorrectly applies these modes without proper security masking. This can result in unintended file permissions, potentially allowing unauthorized access to files or directories.
Red Hat severity: Moderate — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-279.
Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Red Hat fixing advisory: RHSA-2026:57251, RHSA-2026:57254, RHSA-2026:57253, RHSA-2026:57252.
Affected products named by the advisory: Red Hat package: kernel-rt.
Affected versions
No affected-version range was extracted from the source record. The vendor advisory is authoritative — check it before change work.
Official advisory · high-confidence parse· fetched 10 days ago·verify at source
- kernel-0:6.12.0-211.49.1.el10_2
- kernel-rt-0:4.18.0-553.157.1.rt7.498.el8_10
- kernel-0:4.18.0-553.157.1.el8_10
- kernel-0:5.14.0-687.41.1.el9_8
- RHSA-2026:57251
- RHSA-2026:57254
- RHSA-2026:57253
- RHSA-2026:57252
Official advisory · high-confidence parse· fetched 10 days ago·verify at source
Mitigation
Upgrade to a fixed release: kernel-0:6.12.0-211.49.1.el10_2, kernel-rt-0:4.18.0-553.157.1.rt7.498.el8_10, kernel-0:4.18.0-553.157.1.el8_10, kernel-0:5.14.0-687.41.1.el9_8, RHSA-2026:57251, RHSA-2026:57254. That is the remediation for this advisory.
The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.
Official advisory · high-confidence parse· fetched 10 days ago·verify at source
Discussion(0)
No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.
Sign in to join the discussion.