CVE-2026-63729

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.

CVSS v3 6.6 MEDIUM

6.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.7

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://fatihhcelik.github.io/posts/evince-synctex-heap-use-after-free/
https://github.com/TeX-Live/texlive-source/
https://github.com/TeX-Live/texlive-source/commit/002dcd3eac30db5c352f53d4181737961cc7ee9a
https://www.vulncheck.com/advisories/tex-live-synctex-parser-heap-use-after-free-via-malformed-synctex-file

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-21 03:16

Updated : 2026-07-23 15:24

NVD link : CVE-2026-63729

Mitre link : CVE-2026-63729

CVE.ORG link : CVE-2026-63729

JSON object : View

Products Affected

No product.

CWE

CWE-416

Use After Free

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