Description
A vulnerability in B1 Free Archiver v1.5.86 allows files extracted from downloaded archives to bypass Windows Mark of the Web (MotW) protections. When an archive is downloaded from the internet and extracted using B1 Free Archiver, the software fails to propagate the 'Zone.Identifier' alternate data stream to the extracted files. As a result, these files can be executed without triggering Windows Defender SmartScreen warnings or security prompts, enabling untrusted code execution without standard security restrictions.
References3
Metrics
- CVSS 3.1
-
7.3
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - EPSS — exploit probability
- 0% percentile: 27 · as of 13 November 2026
- CWE
- CWE-290
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