libcurl cookie leak for TLDs
============================
Project cURL Security Advisory, September 10th 2014
http://curl.haxx.se/docs/security.html
1. VULNERABILITY
libcurl wrongly allows cookies to be set for Top Level Domains (TLDs), thus
making them apply broader than cookies are allowed. This can allow arbitrary
sites to set cookies that then would get sent to a different and unrelated
site or domain.
2. INFO
Cookie parsing and use is opt-in by applications and is not enabled by
default.
libcurl's cookie parser has no Public Suffix awareness, so apart from
rejecting TLDs from being allowed it might still allow cookies for domains
that are otherwise widely rejected by ordinary browsers. See
https://publicsuffix.org/ for details.
The Common Vulnerabilities and Exposures (CVE) project has assigned the name
CVE-2014-3620 to this issue.
3. AFFECTED VERSIONS
Affected versions: from libcurl 7.31.0 to and including 7.37.1
Not affected versions: libcurl < 7.31.0 and libcurl >= 7.38.0
libcurl is used by many applications, but not always advertised as such!
4. THE SOLUTION
libcurl 7.38.0 doesn't accept cookies set for just a TLD. Note that it does
not add any public suffix awareness apart from that.
A patch for this problem is available at:
http://curl.haxx.se/CVE-2014-3620.patch
5. RECOMMENDATIONS
We suggest you take one of the following actions immediately, in order of
preference:
A - Upgrade to curl and libcurl 7.38.0
B - Apply the patch and rebuild libcurl
C - Avoid using cookies in your application
6. TIME LINE
It was reported to the curl project on August 15th 2014. We contacted
distros@openwall on September 1st.
libcurl 7.38.0 was released on September 10th 2014, coordinated with the
publication of this advisory.
7. CREDITS
Reported by Tim Ruehsen. Patch written by Daniel Stenberg.
Thanks a lot!
--
/ daniel.haxx.se
-------------------------------------------------------------------
List admin: http://cool.haxx.se/list/listinfo/curl-library
Etiquette: http://curl.haxx.se/mail/etiquette.html
