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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/static-web-server/static-web-server/commit/7bf0fd425eb10dac9bf9ef5febce12c4dd039ce1	Patch
https://github.com/static-web-server/static-web-server/security/advisories/GHSA-qhp6-635j-x7r2	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-02-21 10:16

Updated : 2026-02-24 16:55

NVD link : CVE-2026-27480

Mitre link : CVE-2026-27480

CVE.ORG link : CVE-2026-27480

JSON object : View

Products Affected

static-web-server

static_web_server

CWE

CWE-204

Observable Response Discrepancy

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