Description
7-Zip XZ Decompression Heap-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of 7-Zip. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the processing of XZ chunked data. Crafted XZ-compressed data can trigger an overflow of a heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-30169.
Affected products
7-zip: 7-zip
References2
- www.zerodayinitiative.com/advisories/ZDI-26-444/ Third Party AdvisoryVDB Entry
- www.openwall.com/lists/oss-security/2026/07/17/12 Mailing ListThird Party Advisory
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 55 · as of 13 November 2026
- CWE
- CWE-122
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