Bug 1226356

Summary:	VUL-0: CVE-2024-35325: python-ruamel.yaml.clib: libyaml: double-free in yaml_event_delete in /src/libyaml/src/api.c
Product:	[Novell Products] SUSE Security Incidents	Reporter:	Camila Camargo de Matos <camila.matos>
Component:	Incidents	Assignee:	Security Team bot <security-team>
Status:	IN_PROGRESS ---	QA Contact:	Security Team bot <security-team>
Severity:	Major
Priority:	P3 - Medium	CC:	camila.matos, daniel.garcia, security-team, smash_bz
Version:	unspecified
Target Milestone:	---
Hardware:	Other
OS:	Other
URL:	https://smash.suse.de/issue/410664/
Whiteboard:
Found By:	Security Response Team	Services Priority:
Business Priority:		Blocker:	---
Marketing QA Status:	---	IT Deployment:	---
Bug Depends on:
Bug Blocks:	1226342

Description Camila Camargo de Matos 2024-06-14 14:08:27 UTC

+++ This bug was initially created as a clone of Bug #1226342 +++

A vulnerability was found in libyaml up to 0.2.5. Affected by this issue is the function yaml_event_delete of the file /src/libyaml/src/api.c. The manipulation leads to a double-free.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-35325
https://www.cve.org/CVERecord?id=CVE-2024-35325
https://github.com/idhyt/pocs/blob/main/libyaml/CVE-2024-35325.c
https://bugzilla.redhat.com/show_bug.cgi?id=2292350

Comment 1 Camila Camargo de Matos 2024-06-14 17:02:48 UTC

See bug #1226342 for a reference link which is the upstream GitHub issue where this possible vulnerability is being discussed.

Comment 3 Daniel Garcia 2024-06-18 11:33:20 UTC

Possibly not a bug, upstream discussion can be found here:
https://github.com/yaml/libyaml/issues/298

Comment 4 Daniel Garcia 2024-06-26 08:22:33 UTC

The code snippet uses the API in a wrong way, calling yaml_event_delete which shouldn't be called. The correct usage is documented here: https://pyyaml.org/wiki/LibYAML
In the emitter example there is no usage of yaml_event_delete.
yaml_emitter_delete will delete the events itself.

See the discussion here:
https://github.com/yaml/libyaml/issues/297

I've reviewed the embed code in the package and is not affected at all because it is using the API in the correct way.