Bug 1503705 (CVE-2017-1000257)

Summary:	CVE-2017-1000257 curl: IMAP FETCH response out of bounds read
Product:	[Other] Security Response	Reporter:	Andrej Nemec <anemec>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	bmcclain, bodavis, cfergeau, csutherl, dbhole, dblechte, eedri, erik-fedora, gzaronik, hhorak, java-maint, jclere, john.j5live, jorton, kanderso, kdudka, lgao, lsurette, luhliari, mbabacek, mgoldboi, michal.skrivanek, mike, mturk, myarboro, omajid, paul, rh-spice-bugs, rwagner, security-response-team, sherold, srevivo, twalsh, weli, ykaul
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	curl 7.56.1	Doc Type:	If docs needed, set a value
Doc Text:	A buffer overrun flaw was found in the IMAP handler of libcurl. By tricking an unsuspecting user into connecting to a malicious IMAP server, an attacker could exploit this flaw to potentially cause information disclosure or crash the application.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-08 03:29:41 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:	1505232, 1505233, 1505234, 1505284, 1505285, 1505301, 1505302
Bug Blocks:	1503707

Description Andrej Nemec 2017-10-18 14:55:49 UTC

An IMAP FETCH response line indicates the size of the returned data, in number
of bytes. When that response says the data is zero bytes, libcurl would pass
on that (non-existing) data with a pointer and the size (zero) to the
deliver-data function.

libcurl's deliver-data function treats zero as a magic number and invokes
strlen() on the data to figure out the length. The strlen() is called on a
heap based buffer that might not be zero terminated so libcurl might read
beyond the end of it into whatever memory lies after (or just crash) and then
deliver that to the application as if it was actually downloaded.

Introduced with:

https://github.com/curl/curl/commit/ec3bb8f727

External References:

https://curl.haxx.se/docs/adv_20171023.html

Comment 3 Andrej Nemec 2017-10-18 14:58:37 UTC

Mitigation:

Switch off IMAP in `CURLOPT_PROTOCOLS`

Comment 5 Adam Mariš 2017-10-19 10:55:06 UTC

Acknowledgments:

Name: the Curl project
Upstream: Brian Carpenter, the OSS-Fuzz project

Comment 6 Dhiru Kholia 2017-10-23 06:03:04 UTC

Created curl tracking bugs for this issue:

Affects: fedora-all [bug 1505233]


Created mingw-curl tracking bugs for this issue:

Affects: epel-7 [bug 1505232]
Affects: fedora-all [bug 1505234]

Comment 10 Tomas Hoger 2017-11-24 13:23:50 UTC

Upstream commit:

https://github.com/curl/curl/commit/13c9a9ded3ae744a1e11cbc14e9146d9fa427040

OSS-Fuzz issue for this problem:

https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=3586

Comment 11 errata-xmlrpc 2017-11-27 14:51:44 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:3263 https://access.redhat.com/errata/RHSA-2017:3263

Comment 13 errata-xmlrpc 2018-08-16 16:09:13 UTC

This issue has been addressed in the following products:

  Red Hat JBoss Core Services

Via RHSA-2018:2486 https://access.redhat.com/errata/RHSA-2018:2486

Comment 14 errata-xmlrpc 2018-11-13 08:34:43 UTC

This issue has been addressed in the following products:

  Red Hat Software Collections for Red Hat Enterprise Linux 6
  Red Hat Software Collections for Red Hat Enterprise Linux 7
  Red Hat Software Collections for Red Hat Enterprise Linux 7.4 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS

Via RHSA-2018:3558 https://access.redhat.com/errata/RHSA-2018:3558