Description
Microsoft AVML before 0.17.0 could follow a symlink when opening a destination output path on Unix, allowing truncation/overwrite of the symlink target. The destructive effect is performed at open-time via O_TRUNC, and can happen before full input validation completes (“truncation-before-validation”).
References4
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 1% percentile: 45 · as of 15 November 2026
- CWE
- CWE-59
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