An issue was discovered in libxml2 before 2.10.4. When hashing empty dict strings in a crafted XML document, xmlDictComputeFastKey in dict.c can produce non-deterministic values, leading to various logic and memory errors, such as a double free. This behavior occurs because there is an attempt to use the first byte of an empty string, and any value is possible (not solely the '\0' value).

References

• https://nvd.nist.gov/vuln/detail/CVE-2023-29469
• https://gitlab.gnome.org/GNOME/libxml2/-/issues/510
• https://gitlab.gnome.org/GNOME/libxml2/-/releases/v2.10.4
• https://lists.debian.org/debian-lts-announce/2023/04/msg00031.html
• https://security.netapp.com/advisory/ntap-20230601-0006