How severe is CVE-2026-27480?

CVE-2026-27480 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-2026-27480 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-27480?

CVE-2026-27480 affects Static-web-server Static Web Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-27480?

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

Does CVE-2026-27480 have an EU (EUVD) identifier?

Yes. CVE-2026-27480 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7717.

When was CVE-2026-27480 published?

CVE-2026-27480 was published on 2026-02-21 and last updated on 2026-06-17.

CVE-2026-27480

CVE-2026-27480 is a medium-severity vulnerability in Static-web-server Static Web Server 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-204.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-7717
Weakness: CWE-204
Affected product: Static-web-server Static Web Server
Published: 2026-02-21
Last modified: 2026-06-17

Description

Static Web Server (SWS) is a production-ready web server suitable for static web files or assets. In versions 2.1.0 through 2.40.1, a timing-based username enumeration vulnerability in Basic Authentication allows attackers to identify valid users by exploiting early responses for invalid usernames, enabling targeted brute-force or credential-stuffing attacks. SWS checks whether a username exists before verifying the password, causing valid usernames to follow a slower code path (e.g., bcrypt hashing) while invalid usernames receive an immediate 401 response. This timing discrepancy allows attackers to enumerate valid accounts by measuring response-time differences. This issue has been fixed in version 2.41.0.

Frequently asked questions

What is CVE-2026-27480?: Static Web Server (SWS) is a production-ready web server suitable for static web files or assets. In versions 2.1.0 through 2.40.1, a timing-based username enumeration vulnerability in Basic Authentication allows attackers to identify valid users by exploiting early responses for invalid usernames, enabling targeted brute-force or credential-stuffing attacks. SWS checks whether a username exists before verifying the password, causing valid usernames to follow a slower code path (e.g., bcrypt hashing) while invalid usernames receive an immediate 401 response. This timing discrepancy allows attackers to enumerate valid accounts by measuring response-time differences. This issue has been fixed in version 2.41.0.
How severe is CVE-2026-27480?: CVE-2026-27480 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-2026-27480 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-27480?: CVE-2026-27480 affects Static-web-server Static Web Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-27480?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-27480 have an EU (EUVD) identifier?: Yes. CVE-2026-27480 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7717.
When was CVE-2026-27480 published?: CVE-2026-27480 was published on 2026-02-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:static-web-server:static_web_server:*:*:*:*:*:rust:*:*

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