[xml/sgml-pkgs] Bug#1125696: libxml2: CVE-2026-0992: Exponential behavior when handling

[Salvatore Bonaccorso]

Source: libxml2.9
Version: 2.15.1+dfsg-2
Severity: important
Tags: security upstream
Forwarded: https://gitlab.gnome.org/GNOME/libxml2/-/issues/1019
X-Debbugs-Cc: carnil at debian.org, Debian Security Team <team at security.debian.org>

Hi,

The following vulnerability was published for libxml2.

CVE-2026-0992[0]:
| A flaw was found in the libxml2 library. This uncontrolled resource
| consumption vulnerability occurs when processing XML catalogs that
| contain repeated <nextCatalog> elements pointing to the same
| downstream catalog. A remote attacker can exploit this by supplying
| crafted catalogs, causing the parser to redundantly traverse catalog
| chains. This leads to excessive CPU consumption and degrades
| application availability, resulting in a denial-of-service
| condition.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2026-0992
    https://www.cve.org/CVERecord?id=CVE-2026-0992
[1] https://gitlab.gnome.org/GNOME/libxml2/-/issues/1019

Please adjust the affected versions in the BTS as needed.

Regards,
Salvatore