CVE-2026-11771

Summary

OpenVPN version 2.1.0 through 2.6.20 and 2.7_alpha1 through 2.7.4 allows attackers via an off-by-one buffer write in the NTLM proxy authentication to potentially cause a crash via a crafted NTLM response from a malicious proxy server

Affected Software

VendorProductVersion RangeStatus
OpenVPNOpenVPN2.1.0 <= 2.6.20affected
OpenVPNOpenVPN2.7_alpha1 <= 2.7.4affected

Weaknesses

  • CWE-193: CWE-193 Off-by-one error
  • CWE-121: CWE-121 Stack-based buffer overflow
  • CWE-787: CWE-787 Out-of-bounds write

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References