CVE-2025-49794 Libxml: heap use after free (uaf) leads to denial of service (dos)
A use-after-free flaw in libxml2 allows attackers to cause a denial of service via crafted XML documents with specific schematron elements.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-49794?
CVE-2025-49794 is a critical use after free vulnerability in Red Hat OpenShift File Integrity Operator - FIO 1, published on 16 Jun 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A use-after-free vulnerability was found in libxml2. This issue occurs when parsing XPath elements under certain circumstances when the XML schematron has the <sch:name path="..."/> schema elements. This flaw allows a malicious actor to craft a malicious XML document used as input for libxml, resulting in the program's crash using libxml or other possible undefined behaviors.
Weakness: CWE-825
Which versions are affected by CVE-2025-49794?
How do I fix CVE-2025-49794?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2025-49794 being exploited?
There is no known exploitation of CVE-2025-49794 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2025-49794, AZL-64095, AZL-64127, BELL-CVE-2025-49794, DEBIAN-CVE-2025-49794, ECHO-87d5-bef1-89b5 and 2 more.