Is CVE-2026-76781 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-76781 being exploited in the wild.

How severe is CVE-2026-76781?

Medium severity, with a CVSS score of 5.5, published 17 September 2026.

Is there a fix for CVE-2026-76781?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-76781 attacked?

It is attacked with local access or over the network, in a software library.

Am I affected by CVE-2026-76781?

Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-76781: libxml2 NULL pointer dereference in XML catalog parsing

CVE-2026-76781 · Severity: medium · CVSS 5.5 · Published 2026-09-17

libxml2 is a widely-used XML parsing library embedded in many applications and system tools. A specially crafted XML catalog file can crash applications using libxml2 when they attempt to parse it, causing a denial of service that disrupts normal operations. This can be exploited by a local user or by providing a malicious XML file to any application that processes catalogs.

Quick answers

Is CVE-2026-76781 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-76781 being exploited in the wild.
How severe is CVE-2026-76781?: Medium severity, with a CVSS score of 5.5, published 17 September 2026.
Which products and versions are affected?: libxml2 project libxml2.
Is there a fix for CVE-2026-76781?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-76781 attacked?: It is attacked with local access or over the network, in a software library.
Am I affected by CVE-2026-76781?: Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A NULL pointer dereference vulnerability exists in libxml2's XML catalog parsing logic. The flaw occurs when a `nextCatalog` element in an XML catalog is missing its mandatory `catalog` attribute—the parser fails to validate this precondition and attempts to dereference a NULL pointer, causing the application to crash. The attack vector is local or network-based (if the application accepts untrusted XML catalog input), requires no authentication or special privileges, and results in denial of service. Patch availability has not been confirmed from the provided information.

Affected products

libxml2 project libxml2

Timeline

2026-09-17: disclosed

References

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