CVE-2026-81690: verify-usb before 1.4.9 Symlink Directory Traversal Code Execution

Severity: high (CVSS 7.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-27 · updated 2026-09-02
Weakness: CWE-59

Description

openssl-encrypt (pip package) before 1.4.9 contains a symlink-following flaw in its verify-usb v2 added-file allowlist scan. The scan enumerated the drive with rglob(), which in CPython does not descend into symlinked directories and treats the symlink as an ordinary directory, while O_NOFOLLOW on the hash side binds only the final path component. An evil-maid attacker with physical access to the removable drive could replace a tool-tree directory with a symlink to a copy containing byte-identical files plus a planted __pycache__/*.pyc file (which CPython loads in preference to recompiling the clean .py). The planted file is never enumerated, added_files stays 0, and verify-usb reports PASSED, resulting in code execution when the victim runs the portable install. Fixed in 1.4.9 (affects both 1.4.x and 1.5.x lines).

Affected products

jahlives openssl_encrypt: before 1.4.9 — fixed in 1.4.9

How to fix

Upgrade to a fixed version: jahlives openssl_encrypt 1.4.9. Check the vendor advisory for mitigations.

References

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