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TI-2026-73737 Aliases CVE-2026-84790GHSA-6f9v-9427-9fpm

OpenVPN certificate subject field flaw allows user impersonation

Priority LOW 34CWE-158Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Attack requirements
Present
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-290.

Summary

OpenVPN 2.7_alpha1 through 2.7.7 lets a remote authenticated user impersonate other users through a crafted certificate subject field. The weaknesses are CWE-158 (Improper Neutralization of Null Byte or NUL Character) and CWE-290 (Authentication Bypass by Spoofing). CVSS 4.0 scores it 7.6 (HIGH) with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N, and CISA rates exploitation as none, not automatable, with total technical impact. It is not in CISA KEV, and Red Hat lists one product as not affected.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

OpenVPN 2.7_alpha1 through 2.7.7 allows remote authenticated users to impersonate others via a crafted certificate subject field

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00146 3rd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
OpenVPNOpenVPN2.7_alpha1 – 2.7.7—No fix listedCNA
  • OpenVPN VendorOpenVPN Affected 2.7_alpha1 – 2.7.7 Fixed in — No fix listed CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:*——OpenVPN
  • cpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:* Versions — — ·OpenVPN

Remediation

No fixed version is listed for OpenVPN. Restrict access to users you trust and review certificate issuance for crafted subject fields until a fix is released.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-13 Threatist record created from CVE-2026-84790
  2. 2026-10-14 Alias added: GHSA-6f9v-9427-9fpm
  3. 2026-10-14 Priority changed: MEDIUM → LOW
  4. 2026-10-16 Affected versions changed · Red Hat
  5. 2026-10-16 CVSS score added · Red Hat
  6. 2026-10-18 CISA SSVC decision points changed

References

Advisory 1

  • TI-2024-01215 Integer overflow in OpenVPN tap-windows6 CVSS 3.1CRITICAL 9.8
  • TI-2014-04453 Unquoted Windows search path vulnerability in the ptservice service prior to… CVSS 3.1MEDIUM 5.3
  • TI-2022-00467 Authentication bypass in OpenVPN CVSS 3.1CRITICAL 9.8
  • TI-2024-18509 Unrestricted file upload in OpenVPN 2 CVSS 3.1CRITICAL 9.8
  • TI-2024-16468 The interactive service in OpenVPN 2.6.9 and earlier allows the OpenVPN service pipe to… CVSS 3.1HIGH 7.5
  • TI-2023-25309 Use after free in OpenVPN 2 CVSS 3.1CRITICAL 9.8
See all 99 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences