Critical severity · published Apr 11, 2017
CVE-2016-1908
The client in OpenSSH before 7.2 mishandles failed cookie generation for untrusted X11 forwarding and relies on the local X11 server for access-control decisions, which allows…
9.8
CVSS
13.7%
EPSS
No
On KEV
Description
The client in OpenSSH before 7.2 mishandles failed cookie generation for untrusted X11 forwarding and relies on the local X11 server for access-control decisions, which allows remote X11 clients to trigger a fallback and obtain trusted X11 forwarding privileges by leveraging configuration issues on this X11 server, as demonstrated by lack of the SECURITY extension on this X11 server.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)13.7% · higher than 96% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
8.0 · source: NVD
EL
Enterprise Linux Desktop · Redhat
6.0; 7.0 · source: NVD
EL
Enterprise Linux Eus · Redhat
7.2; 7.3; 7.4; 7.5; 7.6; 7.7 · source: NVD
EL
Enterprise Linux Server · Redhat
6.0; 7.0 · source: NVD
EL
Enterprise Linux Server Aus · Redhat
7.2; 7.3; 7.4; 7.6; 7.7 · source: NVD
EL
Enterprise Linux Server Tus · Redhat
7.2; 7.3; 7.6; 7.7 · source: NVD
EL
Enterprise Linux Workstation · Redhat
6.0; 7.0 · source: NVD
LI
Linux · Oracle
6; 7 · source: NVD
OP
Openssh · Openbsd
before 7.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2016-1908
CVE.org
https://www.cve.org/CVERecord?id=CVE-2016-1908
Mailing List
http://openwall.com/lists/oss-security/2016/01/15/13
Third Party Advisory
http://rhn.redhat.com/errata/RHSA-2016-0465.html
Third Party Advisory
http://rhn.redhat.com/errata/RHSA-2016-0741.html
Release Notes
http://www.openssh.com/txt/release-7.2
Third Party Advisory
http://www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.html
Third Party Advisory
http://www.securityfocus.com/bid/84427
More from Debian Linux
10.0
CVE-2025-32433
Erlang/OTP SSH Vulnerable to Pre-Authentication RCE
10.0
CVE-2025-24201
Apple Multiple Products WebKit Out-of-Bounds Write Vulnerability
10.0
CVE-2021-44228
Apache Log4j2 JNDI features do not protect against attacker controlled LDAP and other JNDI related endpoints
10.0
CVE-2015-3306
ProFTPD Improper Access Control Vulnerability
9.8
CVE-2026-24061
GNU InetUtils Argument Injection Vulnerability