CVE-2026-74860 Libxml2: double-free/uaf in libxml2 python bindings
A double-free vulnerability in libxml2 Python bindings allows remote attackers to cause a denial of service via crafted XML documents.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74860?
CVE-2026-74860 is a high-severity use after free vulnerability in Cert Manager support for Red Hat OpenShift release 1.20, published on 8 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A flaw was found in libxml2 with Python bindings enabled. A remote attacker could exploit this vulnerability by providing a specially crafted XML document containing a Document Type Definition (DTD) with enumerated attribute values. This triggers a double-free error in the SAX attributeDecl callback handler, where a string is freed twice. This flaw can lead to a denial of service (DoS) due to a reproducible crash in Python applications using the libxml2 SAX bindings.
Weakness: CWE-763
Which versions are affected by CVE-2026-74860?
How do I fix CVE-2026-74860?
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-2026-74860 being exploited?
There is no known exploitation of CVE-2026-74860 in the wild and no public exploit code.
Sources
Also known as AZL-100941, BELL-CVE-2026-74860, CLSA-2026-1790786185, CLSA-2026-1790833998, CLSA-2026-1791280039, CLSA-2026-1791372460 and 9 more.