Bug 1993517 (CVE-2021-38604)

Summary:	CVE-2021-38604 glibc: NULL pointer dereference in helper_thread() in mq_notify.c while handling NOTIFY_REMOVED messages
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	aoliva, arjun.is, ashankar, bdettelb, caswilli, codonell, dj, fjansen, fweimer, glibc-bugzilla, kaycoth, law, mcermak, mfabian, mnewsome, pdwyer, pfrankli, psegedy, rth, security-response-team, sipoyare, tomckay, vmugicag
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 GNU C library (glibc), where the sysdeps/unix/sysv/linux/mq_notify.c function mishandles certain NOTIFY_REMOVED data, leading to a NULL pointer dereference. The highest threat from this vulnerability is to system availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-05-17 13:45:12 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:	1993518, 1994264
Bug Blocks:	1993519

Description Guilherme de Almeida Suckevicz 2021-08-13 17:19:02 UTC

In librt in the GNU C Library (aka glibc) through 2.34, sysdeps/unix/sysv/linux/mq_notify.c mishandles certain NOTIFY_REMOVED data, leading to a NULL pointer dereference. NOTE: this vulnerability was introduced as a side effect of the CVE-2021-33574 fix.

Reference:
https://sourceware.org/bugzilla/show_bug.cgi?id=28213

Upstream patches:
https://sourceware.org/git/?p=glibc.git;a=commit;h=4cc79c217744743077bf7a0ec5e0a4318f1e6641
https://sourceware.org/git/?p=glibc.git;a=commit;h=b805aebd42364fe696e417808a700fdb9800c9e8

Comment 1 Guilherme de Almeida Suckevicz 2021-08-13 17:19:54 UTC

Created glibc tracking bugs for this issue:

Affects: fedora-all [bug 1993518]

Comment 7 Product Security DevOps Team 2022-05-17 13:45:09 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-2021-38604