CVE-2018-20685

Published: 10 January 2019

In OpenSSH 7.9, scp.c in the scp client allows remote SSH servers to bypass intended access restrictions via the filename of . or an empty filename. The impact is modifying the permissions of the target directory on the client side.

Priority

Medium

CVSS 3 base score: 5.3

Status

Package Release Status
openssh
Launchpad, Ubuntu, Debian 		Upstream
Released (1:7.9p1-5)
Ubuntu 21.04 (Hirsute Hippo)
Released (1:7.9p1-5)
Ubuntu 20.10 (Groovy Gorilla)
Released (1:7.9p1-5)
Ubuntu 20.04 LTS (Focal Fossa)
Released (1:7.9p1-5)
Ubuntu 18.04 LTS (Bionic Beaver)
Released (1:7.6p1-4ubuntu0.2)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (1:7.2p2-4ubuntu2.7)
Ubuntu 14.04 ESM (Trusty Tahr)
Released (1:6.6p1-2ubuntu2.12)
Patches:
Upstream: https://github.com/openssh/openssh-portable/commit/6010c0303a422a9c5fa8860c061bf7105eb7f8b2
Upstream: https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/scp.c.diff?r1=1.197&r2=1.198&f=h
openssh-ssh1
Launchpad, Ubuntu, Debian 		Upstream Ignored
(frozen on openssh 7.5p)
Ubuntu 21.04 (Hirsute Hippo) Needs triage

Ubuntu 20.10 (Groovy Gorilla) Needs triage

Ubuntu 20.04 LTS (Focal Fossa) Needs triage

Ubuntu 18.04 LTS (Bionic Beaver) Needs triage

Ubuntu 16.04 LTS (Xenial Xerus) Does not exist

Ubuntu 14.04 ESM (Trusty Tahr) Does not exist

Notes

AuthorNote
seth-arnold 
openssh-ssh1 is provided for compatibility with old devices that
cannot be upgraded to modern protocols. Thus we may not provide security
support for this package if doing so would prevent access to equipment.
mdeslaur 
The recommended workaround for this issue is to switch to using
sftp instead of scp.

References

Bugs

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