CVE-2026-100542: OpenClaw before 2026.8.1 Extraction Limit Bypass via tar.bz2

Severity: low (CVSS 3.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-26 · updated 2026-09-28
Weakness: CWE-400

Description

OpenClaw (npm package 'openclaw') versions >= 2026.5.28 and < 2026.8.1 mishandle archive listings in the tar.bz2 skill installer: bounded command-output suffixes were treated as complete listings of the archive. A crafted .tar.bz2/.tbz2 skill archive can push prohibited entries out of both retained listings so that entry-count and size checks pass, and the archive is then extracted in full. If an operator approves installation of such a malicious or compromised skill archive, over-limit files or entry counts are persisted in the skill tools directory, consuming disk space or inodes. The issue bypasses OpenClaw's extraction budgets but does not by itself execute archive contents. Fixed in 2026.8.1.

Affected products

OpenClaw: from 2026.5.28 before 2026.8.1 — fixed in 2026.8.1

How to fix

Upgrade to a fixed version: OpenClaw 2026.8.1. Check the vendor advisory for mitigations.

References

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