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CVE PROGRAM SOURCE RECORD6.8 Medium

CVE-2026-49114

ONNX symlink-following and path-traversal arbitrary file write

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

ONNX ONNX

Default version status: unknown

  • 0 to < 1.21.0affected
  • 1.21.0unaffected

References