Bug 2006978 (CVE-2021-39537)

Summary:	CVE-2021-39537 ncurses: heap-based buffer overflow in _nc_captoinfo() in captoinfo.c
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	bdettelb, caswilli, derrick.roach.ctr, fjansen, jwong, kaycoth, mlichvar, psegedy, vkumar, vmugicag, yjog
Target Milestone:	---	Keywords:	Security
Target Release:	---	Flags:	devthomp: needinfo-
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	ncurses 6.2.2	Doc Type:	No Doc Update
Doc Text:	A heap overflow vulnerability has been found in the ncurses package, particularly in the "tic". This flaw results from a lack of proper bounds checking during input processing. By exploiting this boundary error, an attacker can create a malicious file, deceive the victim into opening it using the affected software, and initiate an out-of-bounds write, potentially impacting system availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:		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:	2007372, 2007373, 2007374, 2007620, 2007633, 2007637, 2007638
Bug Blocks:	2006979

Description Guilherme de Almeida Suckevicz 2021-09-22 18:47:17 UTC

An issue was discovered in ncurses through v6.2-1. _nc_captoinfo in captoinfo.c has a heap-based buffer overflow.

Reference:
https://lists.gnu.org/archive/html/bug-ncurses/2020-08/msg00006.html

Comment 3 devthomp 2021-09-23 18:05:20 UTC

full patch with fix:
https://github.com/mirror/ncurses/commit/790a85dbd4a81d5f5d8dd02a44d84f01512ef443#diff-7e95c7bc5f213e9be438e69a9d5d0f261a14952bcbd692f7b9014217b8047340

Of note:
+ add a check for end-of-string in cvtchar to handle a malformed
  string in infotocap (report/testcase by "puppet-meteor").

Comment 4 juneau 2021-09-24 12:39:24 UTC

Marking managed services affected/delegated. Code is present but impact is moderate.