CVE-2026-63729 MEDIUM

CVE-2026-63729: TeX Live SyncTeX Parser Heap Use-After-Free via Malformed SyncTeX File

Vendor Tex Live
Product TeX Live
Weakness CWE-416
Published July 21, 2026
Last update July 21, 2026

CVSS base score

6.8/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

July 21, 2026 CVE published
July 21, 2026 Record updated