{"id":"CVE-2026-27480","summary":"Static Web Server: Timing-Based Username Enumeration in Basic Authentication","details":"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.","aliases":["GHSA-qhp6-635j-x7r2"],"modified":"2026-08-12T03:51:39.361085131Z","published":"2026-02-21T09:14:30.376Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27480.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-204"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27480.json"},{"type":"ADVISORY","url":"https://github.com/static-web-server/static-web-server/security/advisories/GHSA-qhp6-635j-x7r2"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-27480"},{"type":"FIX","url":"https://github.com/static-web-server/static-web-server/commit/7bf0fd425eb10dac9bf9ef5febce12c4dd039ce1"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/static-web-server/static-web-server","events":[{"introduced":"f9b2c9874e12fb10d238b9d1e7613e63c6d93f14"},{"fixed":"ffbb23f2be02f3defb2ddd354d43723d7793bd7b"},{"fixed":"7bf0fd425eb10dac9bf9ef5febce12c4dd039ce1"}],"database_specific":{"source":["CPE_RANGE","REFERENCES"],"cpe":"cpe:2.3:a:static-web-server:static_web_server:*:*:*:*:*:rust:*:*","extracted_events":[{"introduced":"2.1.0"},{"fixed":"2.41.0"}]}}],"versions":["v2.40.1","v2.40.0","v2.39.0","v2.38.1","v2.38.0","v2.37.0","v2.36.1","v2.36.0","v2.35.0","v2.34.0","v2.33.1","v2.33.0","v2.32.2","v2.32.1","v2.32.0","v2.31.1","v2.31.0","v2.30.0","v2.28.0","v2.27.0","v2.26.0","v2.25.0","v2.24.2","v2.24.1","v2.24.0","v2.23.0","v2.22.1","v2.22.0","v2.21.1","v2.21.0","v2.20.2","v2.20.1","v2.20.0","v2.19.0","v2.18.0","v2.17.0","v2.16.0","v2.15.0","v2.14.2","v2.14.1","v2.14.0","v2.13.1","v2.13.0","v2.12.0","v2.11.0","v2.10.0","v2.9.0","v2.8.0","v2.7.1","v2.7.0","v2.6.0","v2.6.0-beta.2","v2.6.0-beta.1","v2.5.0","v2.4.0","v2.3.0","v2.2.0","v2.1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-27480.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"}]}