Bug 1443381 (CVE-2017-7468)

Summary:	CVE-2017-7468 curl: TLS session resumption client cert bypass
Product:	[Other] Security Response	Reporter:	Andrej Nemec <anemec>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	bmcclain, cfergeau, csutherl, dblechte, eedri, erik-fedora, gzaronik, hhorak, jclere, jorton, kdudka, lgao, lsurette, luhliari, mbabacek, mgoldboi, michal.skrivanek, mike, myarboro, omajid, paul, rbalakri, rh-spice-bugs, sardella, sherold, srevivo, twalsh, weli, ykaul, ylavi
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	curl 7.54.0	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2017-04-19 07:32:56 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:	1443383, 1443384
Bug Blocks:

Description Andrej Nemec 2017-04-19 07:31:15 UTC

libcurl would attempt to resume a TLS session even if the client certificate had changed. That is unacceptable since a server by specification is allowed to skip the client certificate check on resume, and may instead use the old identity which was established by the previous certificate (or no certificate).

libcurl supports by default the use of TLS session id/ticket to resume previous TLS sessions to speed up subsequent TLS handshakes. They are used when for any reason an existing TLS connection couldn't be kept alive to make the next handshake faster.

This flaw is a regression and identical to CVE-2016-5419 reported on August 3rd 2016, but affecting a different version range.

External References:

https://curl.haxx.se/docs/adv_20170419.html

Comment 1 Andrej Nemec 2017-04-19 07:32:06 UTC

Created curl tracking bugs for this issue:

Affects: fedora-all [bug 1443384]


Created mingw-curl tracking bugs for this issue:

Affects: fedora-all [bug 1443383]