VULNERABILITY INTELLIGENCE

CVE-2026-49114

CVSS score7.1 HIGH
EPSS probability0.16%
CISA KEVNot currently listed
Published2026-08-21
Last modified2026-10-15
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H

Description

In ONNX before 1.21.0, the 'save_external_data' function builds the external-data file path from the model's external_data location field and opens it for writing without 'O_NOFOLLOW/O_EXCL', after a non-atomic 'os.path.isfile()' check. A local attacker with write access to the directory where a victim serializes external data can deterministically pre-plant a symlink that is being followed, causing the victim's write to append to any file the victim can write, e.g. ~/.ssh/authorized_keys, cron files, or application configs. Fixed in 1.21.0.

Weakness classification

  • 9119a7d8-5eab-497f-8521-727c672e3725: CWE-22

Primary references