CVE-2016-1908: debian debian_linux Improper Authentication
Vulnerability summary
CVE-2016-1908 is a critical (CVSS 9.8) Improper Authentication vulnerability in debian debian_linux. EPSS estimates a 13.74% chance of exploitation in the next 30 days, higher than 96.5% of scored vulnerabilities.
Severe, CVSS 9.8 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 14% (FIRST, 03-11-2026)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 8 · Related 5Timeline
- 11-04-2017PublishedVulnerability first disclosed.
- 29-05-2026Last modifiedVulnerability information updated.
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 metrics
6 scores · 4 sources · 3 versions- NVDNIST9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
13.74%
Chance of exploitation in the next 30 days
Percentile
97%
Versus all other CVEs
30-day change
No change 0.00 pp
From 13.74% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Redhat6 products
- enterprise_linux_desktop6.0 | 7.0
- enterprise_linux_eus7.2 | 7.3 | 7.4 | 7.5 | 7.6 | 7.7
- enterprise_linux_server6.0 | 7.0
- enterprise_linux_server_aus7.2 | 7.3 | 7.4 | 7.6 | 7.7
- enterprise_linux_server_tus7.2 | 7.3 | 7.6 | 7.7
Debian2 products
- openssh< 1:7.2p1-1
- debian_linuxEOL8.0
Openbsd1 product
- openssh< 7.2
Oracle1 product
- linuxEOL6 | 7
Ubuntu1 product
- openssh< 1:6.6p1-2ubuntu2.7
5 vendors · 11 products
References
19 links- www.oracle.com/technetwork/topics/security/linuxbulletinapr2016-2952096.htmlThird Party Advisory
- anongit.mindrot.org/openssh.git/commit/?id=ed4ce82dbfa8a3a3c8ea6fa0db113c71e234416cPatchThird Party Advisory
