UpHeron
All vulnerabilities

Servers and applications

CVE-2008-4109

A certain Debian patch for OpenSSH before 4.3p2-9etch3 on etch; before 4.6p1-1 on sid and lenny; and on other distributions such as SUSE uses functions that are not async-signal-safe in the signal handler for login timeouts, which allows remote attackers to cause a denial of service (connection slot exhaustion) via multiple login attempts. NOTE: this issue exists because of an incorrect fix for…

Severity
Medium 5.0
Published
18 Sept 2008
Last changed
16 Jun 2026
Added to UpHeron
21 Oct 2026
Exploit chance
29% in the next 30 daysHigher than 98% of CVEs. EPSS by FIRST, 12 Nov 2026
Weakness
CWE-264
Attack
Over the network · No login needed
Attacker can
Slow it down
CVSS vector
AV:N/AC:L/Au:N/C:N/I:N/A:P
Sources
NVD

Description

A certain Debian patch for OpenSSH before 4.3p2-9etch3 on etch; before 4.6p1-1 on sid and lenny; and on other distributions such as SUSE uses functions that are not async-signal-safe in the signal handler for login timeouts, which allows remote attackers to cause a denial of service (connection slot exhaustion) via multiple login attempts. NOTE: this issue exists because of an incorrect fix for CVE-2006-5051.

From NVD.

Affected software

SoftwareAffected versions
OpenSSHServers and applications · cpe:a:openbsd:openssh
  • Version 4.4p1
  • Version 4.4
  • Version 4.3p2
  • Version 4.3p1
All 68 release lines
  • Every version up to 4.3p2
  • Every version up to 4.6
  • Version 1.2
  • Version 1.2.1
  • Version 1.2.2
  • Version 1.2.3
  • Version 1.2.27
  • Version 1.3
  • Version 1.5
  • Version 1.5.7
  • Version 1.5.8
  • Version 2
  • Version 2.1
  • Version 2.1.1
  • Version 2.2
  • Version 2.3
  • Version 2.3.1
  • Version 2.5
  • Version 2.5.1
  • Version 2.5.2
  • Version 2.9
  • Version 2.9p1
  • Version 2.9p2
  • Version 2.9.9
  • Version 2.9.9p2
  • Version 3.0
  • Version 3.0p1
  • Version 3.0.1
  • Version 3.0.1p1
  • Version 3.0.2
  • Version 3.0.2p1
  • Version 3.1
  • Version 3.1p1
  • Version 3.2
  • Version 3.2.2
  • Version 3.2.2p1
  • Version 3.2.3p1
  • Version 3.3
  • Version 3.3p1
  • Version 3.4
  • Version 3.4p1
  • Version 3.5
  • Version 3.5p1
  • Version 3.6
  • Version 3.6.1
  • Version 3.6.1p1
  • Version 3.6.1p2
  • Version 3.7
  • Version 3.7.1
  • Version 3.7.1p1
  • Version 3.7.1p2
  • Version 3.8
  • Version 3.8.1
  • Version 3.8.1p1
  • Version 3.9
  • Version 3.9.1
  • Version 3.9.1p1
  • Version 4.0
  • Version 4.0p1
  • Version 4.1
  • Version 4.1p1
  • Version 4.2
  • Version 4.2p1
  • Version 4.3
  • Version 4.3p1
  • Version 4.3p2
  • Version 4.4
  • Version 4.4p1

References

  • NVD https://nvd.nist.gov/vuln/detail/CVE-2008-4109
  • CVE.org https://www.cve.org/CVERecord?id=CVE-2008-4109