DescriptionPuTTY through 0.75 proceeds with establishing an SSH session even if it has never sent a substantive authentication response. This makes it easier for an attacker-controlled SSH server to present a later spoofed authentication prompt (that the attacker can use to capture credential data, and use that data for purposes that are undesired by the client user).
SourceCVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
Debian Bugs990901

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
putty (PTS)buster0.70-6vulnerable
sid, trixie0.79-1fixed

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

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs


[bullseye] - putty <no-dsa> (Minor issue)
[buster] - putty <no-dsa> (Minor issue)
[stretch] - putty <no-dsa> (Minor issue);a=commit;h=1dc5659aa62848f0aeb5de7bd3839fecc7debefa

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