Bug 1532768 (CVE-2017-15132)

Summary:	CVE-2017-15132 dovecot: Auth leaks memory if SASL authentication is aborted
Product:	[Other] Security Response	Reporter:	Pedro Sampaio <psampaio>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	bennie.joubert, dan, janfrode, mhlavink, security-response-team, yozone
Target Milestone:	---	Keywords:	Reopened, Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	dovecot 2.2.34, dovecot 2.3.1	Doc Type:	If docs needed, set a value
Doc Text:	Aborting the process of SASL authentication can lead to a memory leak when the same login processes are reused. An attacker could use this flaw to cause a denial of service due to memory exhaustion.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-10-21 19:52:47 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:	1532769, 1538717, 1551758, 1551759
Bug Blocks:	1538713

Description Pedro Sampaio 2018-01-09 18:54:56 UTC

A flaw was found in dovecot 2.0 up to 2.2.33 and 2.3.0. A abort of SASL authentication results in a memory leak in Dovecot auth client used by login processes. The leak has impact in high performance configuration where same login processes are reused and can cause the process to crash due to memory exhaustion.

Upstream patch:

https://github.com/dovecot/core/commit/1a29ed2f96da1be22fa5a4d96c7583aa81b8b060.patch

https://github.com/dovecot/core/commit/a9b135760aea6d1790d447d351c56b78889dac22.patch

Comment 1 Pedro Sampaio 2018-01-09 18:55:02 UTC

Acknowledgments:

Name: the Dovecot project

Comment 3 Pedro Sampaio 2018-01-25 16:12:20 UTC

Created dovecot tracking bugs for this issue:

Affects: fedora-all [bug 1538717]

Comment 4 Pedro Sampaio 2018-01-25 16:18:57 UTC

Mitigation:

This issue can be mitigated on vulnerable systems by limiting the login process to a single request per process, which is also the default value.

Comment 6 Pedro Yóssis Silva Barbosa 2018-02-19 20:32:56 UTC

A flaw was found in the original upstream fix, this additional fix is needed: 
https://github.com/dovecot/core/commit/a9b135760aea6d1790d447d351c56b78889dac22.patch see this post for details: http://seclists.org/oss-sec/2018/q1/119

Comment 9 Pedro Yóssis Silva Barbosa 2018-03-05 22:04:14 UTC

External References:

https://www.dovecot.org/list/dovecot-news/2018-February/000370.html