CVE-2026-32282 (GCVE-0-2026-32282)

Vulnerability from cvelistv5 – Published: 2026-04-08 01:06 – Updated: 2026-04-13 18:20
VLAI
Title
TOCTOU permits root escape on Linux via Root.Chmod in os in internal/syscall/unix
Summary
On Linux, if the target of Root.Chmod is replaced with a symlink while the chmod operation is in progress, Chmod can operate on the target of the symlink, even when the target lies outside the root. The Linux fchmodat syscall silently ignores the AT_SYMLINK_NOFOLLOW flag, which Root.Chmod uses to avoid symlink traversal. Root.Chmod checks its target before acting and returns an error if the target is a symlink lying outside the root, so the impact is limited to cases where the target is replaced with a symlink between the check and operation.
Severity
6.4 (Medium)
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-13 17:47 UTC
CWE
  • CWE-61 - UNIX Symbolic Link (Symlink) Following
Assigner
References
Impacted products
Vendor Product Version
Go standard library internal/syscall/unix Affected: 0 , < 1.25.9 (semver)
Affected: 1.26.0-0 , < 1.26.2 (semver)
Create a notification for this product.
Credits
Uuganbayar Lkhamsuren (https://github.com/uug4na)
Show details on NVD website
To clipboard 

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