What is CVE-2026-14266?
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.
The record classifies CVE-2026-14266 under weakness class CWE-122. Its CVSS v3 base vector states that the flaw requires local access to the host, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 102 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 7 — HIGH
CVSS:3.0/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H - EPSS (FIRST)
- 0.7% probability of exploitation in the next 30 days, higher than 53.3% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 7.6/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-07-29, last modified 2026-07-30
Is CVE-2026-14266 being exploited?
Weaponised exploit code for CVE-2026-14266 is publicly available. 3 public proof-of-concept repositories are tracked for this identifier. It currently carries a trending score of 38 in the Threadlinqs vulnerability feed.
- 4minx/CVE-2026-14266 (github)
- liyuxuan504-byte/CVE-2026-14266 (github)
- ret2bilibili/CVE-2026-14266 (github)
Affected products and versions
- 7-Zip: 7-Zip
How to fix CVE-2026-14266
No vendor patch reference has been recorded for CVE-2026-14266 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2026-14266
1 tracked threat in the Threadlinqs corpus references CVE-2026-14266, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, FIRST EPSS, public proof-of-concept repositories. Last verified by Threadlinqs on .