Improper Certificate Validation in cURL - CVE-2017-7468

Vulnerability details

The vulnerability allows a remote non-authenticated attacker to manipulate data.

In curl and libcurl 7.52.0 to and including 7.53.1, 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.

Affected software

How to mitigate CVE-2017-7468

External References

• http://www.securityfocus.com/bid/97962
• http://www.securitytracker.com/id/1038341
• https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2017-7468
• https://curl.haxx.se/docs/adv_20170419.html
• https://security.gentoo.org/glsa/201709-14

Related Security Bulletins

• Improper Certificate Validation in curl.haxx.se cURL
• Improper Certificate Validation in curl (Alpine package)
• Arch Linux update for curl
• Gentoo update for cURL
• Fedora 26 update for curl