How severe is CVE-2026-56021?

CVE-2026-56021 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-56021 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-56021?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-56021 have an EU (EUVD) identifier?

Yes. CVE-2026-56021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37908.

When was CVE-2026-56021 published?

CVE-2026-56021 was published on 2026-06-18 and last updated on 2026-06-24.

CVE-2026-56021

CVE-2026-56021 is a medium-severity vulnerability with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-185.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v4: 6.9
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-37908
Weakness: CWE-185
Published: 2026-06-18
Last modified: 2026-06-24

Description

Webmin allows unauthenticated attackers to read the contents of any file ending in .conf within module directories, due to a bypassable regex pattern.

Frequently asked questions

What is CVE-2026-56021?: Webmin allows unauthenticated attackers to read the contents of any file ending in .conf within module directories, due to a bypassable regex pattern.
How severe is CVE-2026-56021?: CVE-2026-56021 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-56021 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-56021?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-56021 have an EU (EUVD) identifier?: Yes. CVE-2026-56021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-37908.
When was CVE-2026-56021 published?: CVE-2026-56021 was published on 2026-06-18 and last updated on 2026-06-24.

References

Other CWE-185 vulnerabilities

CVE-2024-52289 — Critical (CVSS 9.8): authentik is an open-source identity provider. Redirect URIs in the OAuth2 provider in authentik are checked by RegEx…
CVE-2019-12798 — Critical (CVSS 9.8): An issue was discovered in Artifex MuJS 1.0.5. regcompx in regexp.c does not restrict regular expression program size,…
CVE-2026-25896 — Critical (CVSS 9.3): fast-xml-parser allows users to validate XML, parse XML to JS object, or build XML from JS object without C/C++ based…
CVE-2026-4296 — High (CVSS 8.8): An incorrect regular expression vulnerability was identified in GitHub Enterprise Server that allowed an attacker to…
CVE-2018-17984 — High (CVSS 7.8): An unanchored /[a-z]{2}/ regular expression in ISPConfig before 3.1.13 makes it possible to include arbitrary files,…
CVE-2026-33418 — High (CVSS 7.5): DiceBear is an avatar library for designers and developers. Prior to version 9.4.2, the `ensureSize()` function in…

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