What’s Vulnerable › Vulnerabilities

CVE-2026-58052: 7-Zip - Mark-of-the-Web Bypass via RAR5 Alternate Data Stream Name Collision

• Severity: low (CVSS 3.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-06-28 · updated 2026-10-07
• Weakness: CWE-693

Description

7-Zip for Windows through 26.01 fails to preserve the Mark-of-the-Web when extracting a crafted RAR5 archive, because its guard that suppresses an archive-supplied Zone.Identifier stream matches the exact name 'Zone.Identifier' while a RAR5 STM record named ':Zone.Identifier:$DATA' is not matched and NTFS canonicalizes it to the same stream, overwriting the propagated Internet-zone marker with ZoneId=0. A second STM record named '::$DATA' overwrites the extracted file's default data stream, letting an attacker defeat SmartScreen/MotW warnings and spoof file content.

Affected products

• 7-Zip: before 26.03 — fixed in 26.03

How to fix

Upgrade to a fixed version: 7-Zip 26.03. Check the vendor advisory for mitigations.

References

• https://github.com/bikini/exploitarium/tree/main/7zip-rar5-motw-chain-poc
• https://github.com/ip7z/7zip
• https://www.vulncheck.com/advisories/7-zip-mark-of-the-web-bypass-via-rar5-alternate-data-stream-name-collision

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