Name: CVE-2013-4206: Improper Restriction of Operations within the Bounds of a Memory Buffer
Creator: Rapid7
Published: 2013-08-19T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2013-4206, CWE-119, CVSS 6.3, EPSS 0.02475

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.

CVSS Details

CVSS 3.1 Base Score: 6.3

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Debian	—	Upgrade puttyUpgrade filezilla	Jul 30, 2024	Aug 19, 2013
Freebsd	—	Upgrade putty	Dec 10, 2025	Aug 7, 2013
Gentoo Linux	—	Upgrade net-ftp/filezilla.	Oct 30, 2017	Aug 19, 2013
Suse	—	Upgrade filezilla-langUpgrade filezilla	Dec 12, 2013	Aug 19, 2013
Ubuntu	—	Upgrade putty	Nov 19, 2024	Aug 19, 2013

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CVSS Details

Covered by Rapid7

Prioritise with Active Threat Intelligence