Go to homepageCyberStrike

Menu

Star on GitHub · 3.2k
Sign inDownload

CVE-2026-63729

6.6 · MEDIUM

The SyncTeX parser (synctex_parser.c) shipped with TeX Live and embedded by downstream consumers such as GNOME Evince contains a heap use-after-free vulnerability that allows attackers to crash app…

Published Jul 21, 2026CWE-416EPSS 0.18%

Overview

CVE-2026-63729 is a medium-severity vulnerability. It was published on July 21, 2026 and has a CVSS 3.1 base score of 6.6 (MEDIUM).

This vulnerability has a CVSS 3.1 base score of 6.6, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.

Technical description

The SyncTeX parser (synctex_parser.c) shipped with TeX Live and embedded by downstream consumers such as GNOME Evince contains a heap use-after-free vulnerability that allows attackers to crash applications or potentially execute arbitrary code by supplying a malformed .synctex or .synctex.gz file. A malformed SyncTeX file can construct a ref node with a NULL parent pointer, causing the replacement routine to fail to detach the node from its sibling chain, which triggers recursive freeing of live tree nodes and leaves dangling pointers that are later accessed by the parser during document load.

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References

Reffatihhcelik.github.io/posts/evince-synctex-heap-use-after-free/GitHubgithub.com/TeX-Live/texlive-source/GitHubgithub.com/TeX-Live/texlive-source/commit/002dcd3eac30db5c352f53d4181737961cc7ee9aRefwww.vulncheck.com/advisories/tex-live-synctex-parser-heap-use-after-free-via-malformed-synctex-file

How CyberStrike helps

Frequently asked questions

What is CVE-2026-63729?

CVE-2026-63729 is a medium-severity vulnerability. It was published on July 21, 2026 and has a CVSS 3.1 base score of 6.6 (MEDIUM).

How severe is CVE-2026-63729?

This vulnerability has a CVSS 3.1 base score of 6.6, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.

How do I fix or remediate CVE-2026-63729?

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

How can CyberStrike help with CVE-2026-63729?

CyberStrike is an open-source, AI-augmented pentesting engine. Rather than flag a version number, it tests whether an issue like CVE-2026-63729 is actually reachable in your own applications and APIs, then verifies each finding before reporting it. That tells you if the weakness is a real, exploitable risk in your environment or a false positive you can safely deprioritize.

Related MEDIUM CVEs from 2026

View all
Browse by year2026202520242023202220212020201920182017201620152014201320122011201020092008200720062005200420032002200120001999