CVE-2016-0787

NameCVE-2016-0787
DescriptionThe diffie_hellman_sha256 function in kex.c in libssh2 before 1.7.0 improperly truncates secrets to 128 or 256 bits, which makes it easier for man-in-the-middle attackers to decrypt or intercept SSH sessions via unspecified vectors, aka a "bits/bytes confusion bug."
SourceCVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SuSE, Mageia, GitHub code/issues, web search, more)
ReferencesDLA-426-1, DSA-3487-1
NVD severitymedium (attack range: remote)
Debian Bugs815662

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
libssh2 (PTS)wheezy, wheezy (security)1.4.2-1.1+deb7u2fixed
jessie (security), jessie1.4.3-4.1+deb8u1fixed
stretch1.7.0-1fixed
buster, sid1.8.0-1fixed

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

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
libssh2source(unstable)1.5.0-2.1medium815662
libssh2sourcejessie1.4.3-4.1+deb8u1mediumDSA-3487-1
libssh2sourcesqueeze1.2.6-1+deb6u2mediumDLA-426-1
libssh2sourcewheezy1.4.2-1.1+deb7u2mediumDSA-3487-1

Notes

Upstream fix: https://github.com/libssh2/libssh2/commit/ca5222ea819cc5ed797860070b4c6c1aeeb28420
Upstream patch only fixes DH SHA-256 key exchange type, not DH SHA-1

Search for package or bug name: Reporting problems