9.2

CVE-2026-56020: webmin Authentication Bypass by Spoofing

CVSS: 9.2v4.0CriticalAwaiting analysis
Published 18-06-2026Last modified 11-08-2026
Open JSON

Vulnerability summary

CVE-2026-56020 is a critical (CVSS 9.2) Authentication Bypass by Spoofing vulnerability in webmin. EPSS estimates a 0.50% chance of exploitation in the next 30 days, higher than 41.4% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.2/10
010
Critical · v4.0 (CVE.org)
EPSS score
0.50%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 18-06-2026
    PublishedVulnerability first disclosed.
  2. 11-08-2026
    Last modifiedVulnerability information updated.

Description

The Webmin HTTP server (miniserv.pl) allows unauthenticated attackers to impersonate any user with a configured SSL client certificate by sending a forged HTTP header. A remote attacker can spoof certificate DNs and authenticate as any user. Fixed in 2.202.

CVSS metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.50%

Chance of exploitation in the next 30 days

Percentile

41%

Versus all other CVEs

30-day change

0.00 pp

From 0.50% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.50%

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

Webmin1 product

1 vendor · 1 product

References

4 links