A use after free when receiving invalid nick message was found in irssi. External References: https://irssi.org/security/irssi_sa_2017_01.txt Upstream patch: https://github.com/irssi/irssi/commit/6c6c42e3d1b49d90aacc0b67f8540471cae02a1d CVE assignment: http://seclists.org/oss-sec/2017/q1/26
Created irssi tracking bugs for this issue: Affects: fedora-all [bug 1410829] Affects: epel-5 [bug 1410830]
-> The flaw could be triggered either by client itself, or by a specially crafted IRC server. -> The particular part of the part referring to this issue is the following : ----8<---- diff --git a/src/irc/core/irc-nicklist.c b/src/irc/core/irc-nicklist.c index bcb9d1f..f049fe7 100644 --- a/src/irc/core/irc-nicklist.c +++ b/src/irc/core/irc-nicklist.c @@ -314,7 +314,11 @@ static void event_whois_ircop(SERVER_REC *server, const char *data) static void event_nick_invalid(IRC_SERVER_REC *server, const char *data) { if (!server->connected) - server_disconnect((SERVER_REC *) server); + /* we used to call server_disconnect but that crashes + irssi because of undefined memory access. instead, + indicate that the connection should be dropped and + let the irc method to the clean-up. */ + server->connection_lost = server->no_reconnect = TRUE; } static void event_nick_in_use(IRC_SERVER_REC *server, const char *data) ---->8----
Statement: Red Hat Product Security has rated this issue as having Low security impact. This issue is not currently planned to be addressed in future updates. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.