It was found that Elinks performed client credentials delegation during the client-to-server GSS security mechanisms negotiation. A remote, rogue server could use this flaw to impersonate the Elinks client (victim) against the correct (originally intended) server, potentially leading to denial of Elinks tool services for victim client.
This issue affects the versions of the elinks package, as shipped with Red Hat Enterprise Linux 5 and 6. -- This issue affects the versions of the elinks package, as shipped with Fedora release of 16 and 17.
This issue was discovered by Marko Myllynen of Red Hat.
Created attachment 624175 [details] Proposed patch from Kamil Dudka to disable credentials delegation during GSS negotiation
I am working on a new version of the patch, will provide some update shortly.
Created attachment 632061 [details] [PATCH] http_negotiate: do not delegate GSSAPI credentials by default I have proposed a new version of the patch upstream.
Created attachment 633270 [details] fixes supposed to go out with the security advisory An upstream patch allowing to configure trusted servers is going to be applied later, together with some other fixes related to the HTTP authentication.
Created attachment 635073 [details] RHEL-5 backport of the upstream security fixes
Created attachment 635074 [details] RHEL-6 backport of the upstream security fixes
References: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-4545 http://bugzilla.elinks.cz/show_bug.cgi?id=1124 http://repo.or.cz/w/elinks.git/commitdiff/da18694ff7dd0b67dfcb3c417fb0579b1e7d02d7 http://www.debian.org/security/2012/dsa-2592 http://www.securityfocus.com/bid/57065 http://secunia.com/advisories/51569 http://xforce.iss.net/xforce/xfdb/80882
Created elinks tracking bugs for this issue Affects: fedora-all [bug 891566]
elinks-0.12-0.32.pre5.fc18 has been pushed to the Fedora 18 stable repository. If problems still persist, please make note of it in this bug report.
elinks-0.12-0.29.pre5.fc17 has been pushed to the Fedora 17 stable repository. If problems still persist, please make note of it in this bug report.
Acknowledgements: This issue was discovered by Marko Myllynen of Red Hat.
This issue has been addressed in following products: Red Hat Enterprise Linux 6 Red Hat Enterprise Linux 5 Via RHSA-2013:0250 https://rhn.redhat.com/errata/RHSA-2013-0250.html