CVE-2026-54552 (GCVE-0-2026-54552)

Vulnerability from cvelistv5 – Published: 2026-08-18 17:37 – Updated: 2026-08-18 18:44
VLAI
Title
sh _uid does not drop supplementary groups (incomplete privilege drop)
Summary
sh provides Python process launching. Prior to 2.2.4, the _uid option in sh.py performs an incomplete privilege drop on Linux and Unix-like systems. When sh runs from an elevated process and launches a command with _uid set to an unprivileged user, the child changes its UID but can retain the parent process's supplementary groups because the privilege-drop sequence does not fully establish the target user's UID, primary GID, and supplementary groups. The child can therefore retain access to files or resources granted to privileged groups such as root, docker, disk, shadow, or sudo, violating the expected _uid privilege boundary. This issue is fixed in version 2.2.4.
Severity
7.9 (High)
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-18 18:44 UTC
CWE
  • CWE-273 - Improper Check for Dropped Privileges
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7637 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
amoffat sh Affected: < 2.2.4
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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