CVE-2013-4852

Severity: medium (CVSS 6.8 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 3.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2013-08-19 · updated 2026-06-16
Weakness: CWE-189

Description

Integer overflow in PuTTY 0.62 and earlier, WinSCP before 5.1.6, and other products that use PuTTY allows remote SSH servers to cause a denial of service (crash) and possibly execute arbitrary code in certain applications that use PuTTY via a negative size value in an RSA key signature during the SSH handshake, which triggers a heap-based buffer overflow.

Affected products

Debian Linux: 6.0, 7.0, 7.1
Opensuse: 12.3
PuTTY: 0.45, 0.46, 0.47, 0.48, 0.49, 0.50 (+12)
Simon Tatham Putty: through 0.62; 0.53
Winscp: through 5.1.5; 3.7.6, 3.8.2, 3.8_beta, 4.0.4, 4.0.5, 4.2.6 (+26)

References

http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=718779
http://lists.opensuse.org/opensuse-updates/2013-08/msg00035.html
http://lists.opensuse.org/opensuse-updates/2013-08/msg00041.html
http://secunia.com/advisories/54379
http://secunia.com/advisories/54517
http://secunia.com/advisories/54533
http://svn.tartarus.org/sgt?view=revision&sortby=date&revision=9896
http://winscp.net/tracker/show_bug.cgi?id=1017
http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-signature-stringlen.html
http://www.debian.org/security/2013/dsa-2736
http://www.search-lab.hu/advisories/secadv-20130722
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=718779

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