Bug 2186621 (CVE-2023-1872)

Summary:	CVE-2023-1872 kernel: io_uring: use-after-free vulnerability in io_file_get_fixed
Product:	[Other] Security Response	Reporter:	Pedro Sampaio <psampaio>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	acaringi, allarkin, bhu, chwhite, crwood, dbohanno, ddepaula, debarbos, dfreiber, dvlasenk, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jferlan, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, kernel-mgr, ldoskova, lgoncalv, lleshchi, lzampier, nmurray, ptalbert, qzhao, rogbas, rrobaina, rvrbovsk, rysulliv, scweaver, tyberry, vkumar, walters, wcosta, williams, wmealing, ycote
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in the io_uring subsystem of the Linux kernel. The io_file_get_fixed function lacks the presence of ctx->uring_lock, which can lead to a use-after-free vulnerability due to a race condition with fixed files getting unregistered. This flaw allows local privilege escalation.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2023-04-14 13:36:13 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:	2186622
Bug Blocks:	2186623

Description Pedro Sampaio 2023-04-13 21:03:57 UTC

A use-after-free vulnerability in the Linux Kernel io_uring system can be exploited to achieve local privilege escalation.

The io_file_get_fixed function lacks the presence of ctx->uring_lock which can lead to a Use-After-Free vulnerability due a race condition with fixed files getting unregistered.

We recommend upgrading past commit da24142b1ef9fd5d36b76e36bab328a5b27523e8.

References:

https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=da24142b1ef9fd5d36b76e36bab328a5b27523e8
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-5.10.y&id=08681391b84da27133deefaaddefd0acfa90c2be

Comment 1 Pedro Sampaio 2023-04-13 21:04:20 UTC

Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2186622]

Comment 2 Product Security DevOps Team 2023-04-14 13:36:10 UTC

This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2023-1872

Comment 3 Justin M. Forbes 2023-04-19 11:45:23 UTC

This was fixed for Fedora with the 5.17.3 stable kernel updates.