7.5

CVE-2021-4234: openvpn openvpn_access_server

CVSS: 7.5v3.1HighModified
Published 06-07-2022Last modified 03-08-2024
Open JSON

Vulnerability summary

CVE-2021-4234 is a high (CVSS 7.5) vulnerability in openvpn openvpn_access_server. EPSS estimates a 0.89% chance of exploitation in the next 30 days, higher than 58.8% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
0.89%
0%100%
Low · +0.03 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 06-07-2022
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

2 scores · 1 source · 2 versions

EPSS trend

Probability

0.89%

Chance of exploitation in the next 30 days

Percentile

59%

Versus all other CVEs

30-day change

+0.03 pp

From 0.87% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.89%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Openvpn1 product

1 vendor · 1 product

References

1 links