Bug 1836362 (CVE-2020-12783)

Summary:	CVE-2020-12783 exim: out-of-bounds read in the SPA authenticator can lead to SPA/NTLM authentication bypass in auths/spa.c and auths/auth-spa.c
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	bennie.joubert, dwmw2, jskarvad, mbenatto, tremble
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	exim 4.94	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in exim in versions through 4.93. An out-of-bounds memory read in the SPA authenticator was found that could result in a SPA/NTLM authentication bypass. The highest threat from this vulnerability is to data confidentiality.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-05-20 21:19:23 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:	1836363, 1836364
Bug Blocks:	1836365

Description Guilherme de Almeida Suckevicz 2020-05-15 17:22:03 UTC

Exim through 4.93 has an out-of-bounds read in the SPA authenticator that could result in SPA/NTLM authentication bypass in auths/spa.c and auths/auth-spa.c.

Reference:
https://bugs.exim.org/show_bug.cgi?id=2571

Upstream commits:
https://git.exim.org/exim.git/commit/57aa14b216432be381b6295c312065b2fd034f86
https://git.exim.org/exim.git/commit/a04174dc2a84ae1008c23b6a7109e7fa3fb7b8b0

Comment 1 Guilherme de Almeida Suckevicz 2020-05-15 17:22:22 UTC

Created exim tracking bugs for this issue:

Affects: epel-all [bug 1836364]
Affects: fedora-all [bug 1836363]

Comment 6 Todd Cullum 2020-05-20 20:03:00 UTC

Statement:

This flaw does not affect Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, or Red Hat Enterprise Linux 8.

Comment 7 Product Security DevOps Team 2020-05-20 21:19:23 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-2020-12783