| Name | CVE-2020-1730 |
| Description | A flaw was found in libssh versions before 0.8.9 and before 0.9.4 in the way it handled AES-CTR (or DES ciphers if enabled) ciphers. The server or client could crash when the connection hasn't been fully initialized and the system tries to cleanup the ciphers when closing the connection. The biggest threat from this vulnerability is system availability. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 956308 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| libssh (PTS) | jessie, jessie (lts) | 0.6.3-4+deb8u6 | fixed |
| stretch (security) | 0.7.3-2+deb9u3 | fixed |
| stretch (lts), stretch | 0.7.3-2+deb9u4 | fixed |
| buster (security), buster, buster (lts) | 0.8.7-1+deb10u2 | fixed |
| bullseye (security), bullseye | 0.9.8-0+deb11u1 | fixed |
| bookworm (security), bookworm | 0.10.6-0+deb12u1 | fixed |
| sid, trixie | 0.11.1-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| libssh | source | jessie | (not affected) | | | |
| libssh | source | stretch | (not affected) | | | |
| libssh | source | buster | 0.8.7-1+deb10u1 | | | |
| libssh | source | (unstable) | 0.9.4-1 | | | 956308 |
Notes
[stretch] - libssh <not-affected> (Vulnerable code introduced later)
[jessie] - libssh <not-affected> (Vulnerable code introduced later)
https://www.libssh.org/security/advisories/CVE-2020-1730.txt
https://bugs.libssh.org/T213
Introduced by: https://git.libssh.org/projects/libssh.git/commit/?id=84a85803b4c83b8dac03b0d0aba58b48c98253e6 (libssh-0.8.0)
Fixed by: https://git.libssh.org/projects/libssh.git/commit/?id=b36272eac1b36982598c10de7af0a501582de07a