- Reported
-
- Issued
-
- Package
-
librsvg
(crates.io)
- Type
-
Vulnerability
- Categories
-
- Keywords
-
#uaf
- References
-
- Patched
-
>=2.63.2>=2.62.4, <2.62.90
Description
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.
Advisory available under CC0-1.0
license.