CVE-2004-1440

Severity: high (CVSS 7.5 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 4.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2004-12-31 · updated 2026-06-16

Description

Multiple heap-based buffer overflows in the modpow function in PuTTY before 0.55 allow (1) remote attackers to execute arbitrary code via an SSH2 packet with a base argument that is larger than the mod argument, which causes the modpow function to write memory before the beginning of its buffer, and (2) remote malicious servers to cause a denial of service (client crash) and possibly execute arbitrary code via a large bignum during authentication.

Affected products

PuTTY: 0.48, 0.49, 0.50, 0.51, 0.52, 0.53 (+2)

References

http://marc.info/?l=bugtraq&m=109167869528138&w=2
http://secunia.com/advisories/12212/
http://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html
http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-modpow.html
http://www.gentoo.org/security/en/glsa/glsa-200408-04.xml
http://www.securityfocus.com/bid/10850
https://exchange.xforce.ibmcloud.com/vulnerabilities/16885
http://marc.info/?l=bugtraq&m=109167869528138&w=2
http://secunia.com/advisories/12212/
http://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html
http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-modpow.html
http://www.gentoo.org/security/en/glsa/glsa-200408-04.xml

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