#VU111221 Use-after-free in Libxml2 - CVE-2025-49794

Vulnerability identifier: #VU111221

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-49794

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Libxml2
Universal components / Libraries / Libraries used by multiple products

Vendor: Gnome Development Team

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a use-after-free error within the xmlSchematronGetNode() function when processing XPath expressions in Schematron schema elements schematron.c. A remote attacker can pass specially crafted XML input to the application and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Libxml2: 2.0.0 - 2.14.4

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External links
https://bugzilla.redhat.com/show_bug.cgi?id=2372373
https://gitlab.gnome.org/GNOME/libxml2/-/issues/931
https://gitlab.gnome.org/GNOME/libxml2/-/commit/71e1e8af5ee46dad1b57bb96cfbf1c3ad21fbd7b

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.