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[SECURITY ADVISORY] curl: Incorrect reuse of client certificates
From: Daniel Stenberg <daniel () haxx se>
Date: Wed, 7 Sep 2016 13:39:36 +0200 (CEST)
Incorrect reuse of client certificates ======================================
Project cURL Security Advisory, September 7th 2016 - [Permalink](https://curl.haxx.se/docs/adv_20160907.html) VULNERABILITY ------------- libcurl built on top of NSS (Network Security Services) incorrectly re-used client certificates if a certificate from file was used for one TLS connection but no certificate set for a subsequent TLS connection. While the symptoms are similar to CVE-2016-5420 (Re-using connection with wrong client cert), this vulnerability was caused by an implementation detail of the NSS backend in libcurl, which is orthogonal to the cause of CVE-2016-5420. We are not aware of any exploit of this flaw. INFO ---- This flaw also affects the curl command line tool. The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2016-7141 to this issue. AFFECTED VERSIONS ----------------- This flaw is present in curl and libcurl only if they are built with the support for NSS and only if the libnsspem.so library is available at run-time. - Affected versions: libcurl 7.19.6 to and including 7.50.1 - Not affected versions: libcurl >= 7.50.2 libcurl is used by many applications, but not always advertised as such! THE SOLUTION ------------ A fix for this flaw is included in libcurl 7.50.2 via [commit `curl-7_50_2~32`](https://github.com/curl/curl/commit/curl-7_50_2~32). For older releases of libcurl there is a [patch for CVE-2016-7141](https://curl.haxx.se/CVE-2016-7141.patch). RECOMMENDATIONS --------------- We suggest you take one of the following actions immediately, in order of preference: A - Apply the patch on the source code of libcurl and rebuild. B - Configure libcurl to use a different TLS backend and rebuild. C - Use certificates from NSS database instead of loading them from files. TIME LINE --------- This flaw was reported by Red Hat on August 22nd. The patch fixing the flaw was published on September 5th. CVE-2016-7141 was assigned to this flaw on September 6th. This advisory was published on September 7th. CREDITS ------- Reported by Red Hat. Security advisory coordinated by Daniel Stenberg. Thanks a lot! -- / daniel.haxx.se
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- [SECURITY ADVISORY] curl: Incorrect reuse of client certificates Daniel Stenberg (Sep 07)