Bug 2189896 (CVE-2023-30549)

Summary:	CVE-2023-30549 apptainer: use after free flaw when mounting ext4
Product:	[Other] Security Response	Reporter:	Vipul Nair <vinair>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED UPSTREAM	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	Keywords:	Security
Target Milestone:	---
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2023-04-26 16:09:52 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:	2189640, 2189897, 2189898
Bug Blocks:	2189891

Description Vipul Nair 2023-04-26 10:38:23 UTC

There is an ext4 use-after-free flaw that is exploitable through versions of Apptainer < 1.1.0, installations that include apptainer-suid < 1.1.8, and all versions of Singularity in their default configurations on older operating systems where that CVE has not been patched. That includes Red Hat Enterprise Linux 7, Debian 10 buster (unless the linux-5.10 package is installed), Ubuntu 18.04 bionic and Ubuntu 20.04 focal. Use-after-free flaws in the kernel can be used to attack the kernel for denial of service and potentially for privilege escalation.

Apptainer 1.1.8 includes a patch that by default disables mounting of extfs filesystem types in setuid-root mode, while continuing to allow mounting of extfs filesystems in non-setuid "rootless" mode using fuse2fs.

https://github.com/apptainer/apptainer/security/advisories/GHSA-j4rf-7357-f4cg
https://github.com/apptainer/apptainer/commit/5a4964f5ba9c8d89a0e353b97f51fd607670a9f7
https://security-tracker.debian.org/tracker/CVE-2022-1184
https://github.com/apptainer/apptainer/releases/tag/v1.1.8

Comment 1 Vipul Nair 2023-04-26 10:40:04 UTC

Created apptainer tracking bugs for this issue:

Affects: epel-all [bug 2189898]
Affects: fedora-all [bug 2189897]

Comment 2 Product Security DevOps Team 2023-04-26 16:09:50 UTC

This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.