Bug 2519782

Summary: CVE-2026-76781 libxml2: libxml2: NULL pointer dereference parsing nextCatalog without catalog attribute [fedora-all]
Product: [Fedora] Fedora Reporter: Ganesh <gnaik>
Component: libxml2Assignee: David King <amigadave>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: rawhideCC: amigadave
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["92b34854-680a-43a6-b19d-83bae9c17936"]}
Fixed In Version: libxml2-2.15.4-1.fc45 Doc Type: ---
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2026-10-03 00:23:33 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 2519776    

Description Ganesh 2026-08-19 17:30:24 UTC
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

A NULL pointer dereference flaw was found in libxml2 XML catalog parsing. When a catalog contains a nextCatalog element without the mandatory catalog attribute, xmlParseXMLCatalogOneNode() returns NULL, but the nextCatalog deduplication loop dereferences the entry before the existing NULL check, crashing the application.

Comment 1 Fedora Update System 2026-09-12 09:34:54 UTC
FEDORA-2026-081eb18404 (0ad-0.28.0-7.fc46, abiword-3.0.8-6.fc46, and 480 more) has been submitted as an update to Fedora 46.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-081eb18404

Comment 2 Fedora Update System 2026-09-13 17:35:35 UTC
FEDORA-2026-081eb18404 (0ad-0.28.0-7.fc46, abiword-3.0.8-6.fc46, and 483 more) has been pushed to the Fedora 46 stable repository.
If problem still persists, please make note of it in this bug report.

Comment 3 Fedora Update System 2026-09-25 07:06:54 UTC
FEDORA-2026-91259c13b9 (0ad-0.28.0-7.fc45, abiword-3.0.8-6.fc45, and 486 more) has been submitted as an update to Fedora 45.
https://bodhi.fedoraproject.org/updates/FEDORA-2026-91259c13b9

Comment 4 Fedora Update System 2026-09-26 01:46:47 UTC
FEDORA-2026-91259c13b9 has been pushed to the Fedora 45 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-91259c13b9`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-91259c13b9

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 5 Fedora Update System 2026-09-29 01:33:31 UTC
FEDORA-2026-91259c13b9 has been pushed to the Fedora 45 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-91259c13b9`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-91259c13b9

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 6 Fedora Update System 2026-09-30 01:52:07 UTC
FEDORA-2026-91259c13b9 has been pushed to the Fedora 45 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --refresh --advisory=FEDORA-2026-91259c13b9`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2026-91259c13b9

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 7 Fedora Update System 2026-10-03 00:23:33 UTC
FEDORA-2026-91259c13b9 (0ad-0.28.0-7.fc45, abiword-3.0.8-6.fc45, and 488 more) has been pushed to the Fedora 45 stable repository.
If problem still persists, please make note of it in this bug report.