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TI-2021-03094 Aliases CVE-2021-4234GHSA-qvww-9jm9-f3pm

OpenVPN Access Server 2.10 and prior versions are susceptible to resending multiple…

Priority LOW 35CWE-406Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

OpenVPN Access Server 2.10 and prior versions are susceptible to resending multiple packets in a response to a reset packet sent from the client which the client again does not respond to, resulting in a limited amplification attack.

Why it matters now

EPSS 0.00916 60th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—OpenVPN Access Server2.10 and prior version—No fix listedCNA
  • OpenVPN Access Server Vendor— Affected 2.10 and prior version Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:openvpn:openvpn_access_server:*:*:*:*:*:*:*:*before 2.11.0VulnerableOpenVPN
  • cpe:2.3:a:openvpn:openvpn_access_server:*:*:*:*:*:*:*:* Versions before 2.11.0 Vulnerable ·OpenVPN

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-4234
  2. 2026-10-03 Alias added: GHSA-qvww-9jm9-f3pm

References

Advisory 1

  • TI-2023-25309 Use after free in OpenVPN 2 CVSS 3.1CRITICAL 9.8
  • TI-2020-07187 OpenVPN Access Server 2.8.x before 2.8.1 allows LDAP authentication bypass (except when a… CVSS 3.1CRITICAL 9.8
  • TI-2006-01578 OpenVPN 2.0 through 2.0.5 allows remote malicious servers to execute arbitrary code on… CVSS 2.0HIGH 9.0
  • TI-2023-25308 Using the --fragment option in certain configuration setups OpenVPN version 2.6.0 to… CVSS 3.1HIGH 7.5
  • TI-2005-03217 Format string vulnerability in the foreign_option function in options.c for OpenVPN 2.0.x… CVSS 2.0HIGH 7.5
  • TI-2025-02715 OpenVPN Access Server 2.7.2 through 3.1.0 accepts bare line-feed sequences inside HTTP… CVSS 4.0MEDIUM 6.9
See all 20 →

Sources

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