Librsvg: Use-after-free when XML includes have duplicated entities

Librsvg uses libxml2, a C library, to parse XML. When librsvg parses an SVG document which has a nested Xinclude, an XML entity declaration with a duplicate name as an existing one can cause a use-after-free error. While libxml2 is expanding an internal entity, a recursive XInclude can parse another document that declares an entity with the same name. Both parses use the same `XmlState` entity map on the librsvg side. `entity_insert()` replaces the first entry, whose `Drop` implementation calls `xmlFreeNode()`. The outer `xmlCtxtParseEntity()` then keeps using the freed 144-byte `xmlEntity`. The included parse should not free an entity that the outer parser is still using. The fix is in commit 8a1b0cd319e9af2d1e9cf878081dd77f227a0504, where librsvg will no longer free xmlEntity pointers that libxml2 is still using.

Source published

22 Oct 2026 15:52:48 UTC

Source modified

22 Oct 2026 16:10:47 UTC

Observed here

24 Oct 2026 13:19:54 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Publisher rating · HIGH