CVE-2013-4206

Name	CVE-2013-4206
Description	Heap-based buffer underflow in the modmul function in sshbn.c in PuTTY before 0.63 allows remote SSH servers to cause a denial of service (crash) and possibly trigger memory corruption or code execution via a crafted DSA signature, which is not properly handled when performing certain bit-shifting operations during modular multiplication.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DSA-2736-1
Debian Bugs	719070

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
filezilla (PTS)	bookworm	3.63.0-1+deb12u3	fixed
	trixie	3.68.1-1	fixed
	forky, sid	3.71.0-1	fixed
putty (PTS)	bookworm	0.78-2+deb12u2	fixed
	bookworm (security)	0.78-2+deb12u1	fixed
	trixie	0.83-3	fixed
	forky, sid	0.85-3	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
filezilla	source	(unstable)	3.7.3-1	low		719070
putty	source	squeeze	0.60+2010-02-20-1+squeeze2		DSA-2736-1
putty	source	wheezy	0.62-9+deb7u1		DSA-2736-1
putty	source	(unstable)	0.63-1

Notes

[squeeze] - filezilla <no-dsa> (Minor issue)
[wheezy] - filezilla <no-dsa> (Minor issue)
http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-modmul.html