Bug 2054089 (CVE-2021-45444)

Summary:	CVE-2021-45444 zsh: Prompt expansion vulnerability
Product:	[Other] Security Response	Reporter:	Sandipan Roy <saroy>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	dmaphy, james.antill, j, kdudka, svashisht, trathi
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	zsh 5.8.1	Doc Type:	If docs needed, set a value
Doc Text:	A vulnerability was found in zsh in the parsecolorchar() function of prompt.c file. This flaw allows an attacker to perform code execution if they control a command output inside the prompt, as stated by a %F%K argument. This occurs because of recursive PROMPT_SUBST expansion.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2022-05-11 16:46:54 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:	2054090, 2054569, 2054570, 2056774
Bug Blocks:	2054091

Description Sandipan Roy 2022-02-14 07:12:49 UTC

https://www.zsh.org/mla/announce/msg00133.html
https://bugs.gentoo.org/833252

From the release announcement:
>This is a stable security release with a few bug fixes, including one
>for CVE-2021-45444, a vulnerability in prompt expansion which could be
>exploited through e.g. VCS_Info to execute arbitrary shell commands
>without a user's knowledge. All sites are encouraged to update from
>zsh 5.8. A partial work-around which can be applied within a running
>shell is provided in the source distribution for those who are unable
>to update their shell binaries.

Comment 1 Sandipan Roy 2022-02-14 07:13:14 UTC

Created zsh tracking bugs for this issue:

Affects: fedora-all [bug 2054090]

Comment 10 errata-xmlrpc 2022-05-10 15:29:35 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2022:2120 https://access.redhat.com/errata/RHSA-2022:2120

Comment 11 Product Security DevOps Team 2022-05-11 16:46:51 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-2021-45444