CVE-2026-31710 (GCVE-0-2026-31710)

Vulnerability from cvelistv5 – Published: 2026-05-01 13:56 – Updated: 2026-09-21 13:13
VLAI
Title
smb: client: fix dir separator in SMB1 UNIX mounts
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix dir separator in SMB1 UNIX mounts When calling cifs_mount_get_tcon() with SMB1 UNIX mounts, @cifs_sb->mnt_cifs_flags needs to be read or updated only after calling reset_cifs_unix_caps(), otherwise it might end up with missing CIFS_MOUNT_POSIXACL and CIFS_MOUNT_POSIX_PATHS bits. This fixes the wrong dir separator used in paths caused by the missing CIFS_MOUNT_POSIX_PATHS bit in cifs_sb_info::mnt_cifs_flags.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 4fc3a433c13944ee5766ec5b9bf6f1eb4d29b880 , < fbbfcf35e1ee3396631f3dc6214cb626aa9814c3 (git)
Affected: 4fc3a433c13944ee5766ec5b9bf6f1eb4d29b880 , < c4d3fc5844d685441befd0caaab648321013cdfd (git)
Affected: 9d9f6e06123001208cd8ae6332c7e814ab709169 (git)
Affected: 6.18.53 , < 6.19 (semver)
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Linux Linux Affected: 7.0
Unaffected: 0 , < 7.0 (semver)
Unaffected: 7.0.2 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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