Home/CVE/OpenVPN before 2.0.1, when running with "verb 0" and without TLS authentication, does not properly flush the OpenSSL err
CVE

CVE-2005-2531

OpenVPN before 2.0.1, when running with "verb 0" and without TLS authentication, does not properly flush the OpenSSL err

OpenVPN before 2.0.1, when running with "verb 0" and without TLS authentication, does not properly flush the OpenSSL error queue when a client fails certificate authentication to the server and causes the error to be processed by the wrong client, which allows remote attackers to cause a denial of service (client disconnection) via a large number of failed authentication attempts.

MEDIUM · CVSS 5 EPSS 0.0141
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
▤

Affected Products & Versions

1
openvpnall versions
▣

Scoring & Timeline

5
MEDIUM · CVSS v2 (legacy) · cve@mitre.org
View on NVD
This CVE predates CVSS v3; the legacy v2 score is shown so triage still has a severity to work with.
v2 Vector
AV:N/AC:L/Au:N/C:N/I:N/A:P
Published to NVD24 Aug 2005 · 04:00 AM
🔗

References & Sources

7
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
http://openvpn.net/changelog.html
http://secunia.com/advisories/16463
http://secunia.com/advisories/17103
http://www.debian.org/security/2005/dsa-851
http://www.mandriva.com/security/advisories?name=MDKSA-2005:145PatchVendor Advisory
http://www.novell.com/linux/security/advisories/2005_20_sr.html
Intelligence Graph · click any node to traverse
CVETechnique ActorTool Family
drag to reposition · click any node to traverse · button top-right enlarges
External lookups - second-class, for what we don’t hold ourselves
NVDCVE.orgCISAVulnersExploit-DBGitHub PoCVulnCheck KEVGreyNoise
Vulnerabilities
CISA KEV catalog
CWE weaknesses
CAPEC attack patterns
Package vulnerabilities
Threat intelligence
Threat actors
Tools & malware
ATT&CK techniques
IOCs
Detection & defense
Sigma rules
YARA rules
Atomic Red Team tests
D3FEND countermeasures
Compliance
NIST 800-53
ISO 27001:2022
SOC 2 TSC
PCI-DSS v4.0
CIS Controls v8.1
About
All capabilities
Live statistics
Data sources
Privacy policy
Terms of service
threatengine.sh  ·  Open-source threat intelligence platform  ·  100+ authoritative sources  ·  Every fact traces to its origin