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By Date By Thread Irssi Security Advisory CVE-2016-7044+CVE-2016-7045 From: "A.N." <ailin () devio us>

Date: Wed, 21 Sep 2016 21:27:46 +0200

We are sad to have to announce the following security issue: Canonical URL http://irssi.org/security/irssi_sa_2016.txt heap corruption and missing boundary checks =========================================== CWE Classification: CWE-20, CWE-823, CWE-126, CWE-122 CVE-2016-7044 [1] was assigned to bug 1 CVE-2016-7045 [2] was assigned to bug 2 Description ----------- Gabriel Campana and Adrien Guinet from Quarkslab reported two remote crash and heap corruption vulnerabilites in Irssi's format parsing code. They also provided us with proof of concept exploit code and patches to fix those issues. Impact ------ Remote crash and heap corruption. Remote code execution seems difficult since only Nuls are written. Detailed analysis ----------------- Based on analysis Provided by Gabriel Campana and Adrien Guinet from Quarkslab: Bug 1 The unformat_24bit_color() function is called by format_send_to_gui() to decode 24bit color codes into their components. The pointer is advanced unconditionally without checking if a complete code was supplied. Thus, after the return of unformat_24bit_color(), ptr might be invalid and point out of the buffer. Bug 2 The format_send_to_gui() function does not validate the length of the string before incrementing the `ptr' pointer in all cases. If that happens, the pointer `ptr' can be incremented twice and thus end past the boundaries of the original `dup' buffer. Affected versions ----------------- Irssi 0.8.17-beta up to and including 0.8.19 up to 0.8.19-219-g52fedea Bug 1 affects only Irssis compiled with true-color enabled. Bug 2 affects all Irssis regardless of compilation flags. Fixed in -------- Irssi 0.8.20 Recommended action ------------------ Upgrade to Irssi 0.8.20. Irssi 0.8.20 is a maintenance release without any new features. After installing the updated packages, one can issue the /upgrade command to load the new binary. TLS connections will require /reconnect. If the buf.pl script is loaded and symlinked into ~/.irssi/scripts/autorun, text buffer content will be saved and restored. Fallback action --------------- Distributions which need to remain on Irssi 0.8.17 are strongly urged to apply the patch and provide updated packages. Those totally unable to upgrade, but with Perl support enabled in their Irssi, can load the following script and add it to ~/.irssi/scripts/autorun as a first aid to mitigating these issues: https://irssi.org/security/sa_patch.pl Patch ----- https://github.com/irssi/irssi/commit/295a4b77f07f14602eeaa371f00ddbf09 910c82b References ---------- [1] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7044 [2] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7045 By Date By Thread Current thread: Irssi Security Advisory CVE-2016-7044+CVE-2016-7045 A.N. (Sep 21)