PT-2026-21333 · Unknown · Static Web Server

Naoyashiga · Published 2026-02-20 · Updated 2026-02-24 · CVE-2026-27480

Positive Technologies (AI Summary)

CVSS v3.1

5.3

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Name of the Vulnerable Software and Affected Versions Static Web Server versions 2.1.0 through 2.40.1

Description Static Web Server (SWS) has a timing-based username enumeration issue in Basic Authentication. The server checks if a username exists before verifying the password. Valid usernames trigger a slower code path, such as bcrypt hashing, while invalid usernames receive an immediate 401 response. This timing difference allows attackers to identify valid accounts by measuring response-time differences, enabling targeted brute-force or credential-stuffing attacks. The server validates the provided username before password verification. An attacker can distinguish between existing and non-existing accounts by analyzing response times to the authentication endpoint.

Recommendations Versions 2.1.0 through 2.40.1 should be updated to version 2.41.0 or later.

Exploit

Fix

Weakness Enumeration

CWE-204

Related Identifiers

CVE-2026-27480

GHSA-QHP6-635J-X7R2

Affected Products

Static Web Server

References · 15

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27480.json · Exploit
• 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 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-27480 · Security Note
• https://osv.dev/vulnerability/CVE-2026-27480 · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-qhp6-635j-x7r2 · Vendor Advisory
• https://github.com/static-web-server/static-web-server · Note
• https://reddit.com/r/VulnMatter/comments/1rdh91b/resumen_diario_de_vulnerabilidades_24022026 · Reddit Post
• https://twitter.com/_cvereports/status/2025188922754510938 · Twitter Post
• https://twitter.com/VulmonFeeds/status/2025175496208650626 · Twitter Post
• https://reddit.com/r/VulnMatter/comments/1raarn5/resumen_diario_de_vulnerabilidades_20022026 · Reddit Post
• https://t.me/CVEtracker/45370 · Telegram Post
• https://t.me/cveNotify/152714 · Telegram Post
• https://twitter.com/CVEnew/status/2025154167832994054 · Twitter Post
• https://t.me/cveNotify/153013 · Telegram Post