Vulnerability · CVE-2026-27480
Static Web Server (SWS) is a production-ready web server suitable for static web files or assets.
Published Feb 21, 2026 · catalog updated Jun 17, 2026 · static web server
Check if you run it
No confirmed exploitation is on record for CVE-2026-27480. EPSS is 0.43%. Act only if a listed version of static web server is installed.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Medium5.3
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.43%
- Remediation
- Advisory link
- Affected products
- cpe static-web-server/static web server
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe static-web-server/static web serverversion unspecified
How to fix CVE-2026-27480
Recommended remediation
A patch or advisory reference is linked. Open the original publisher for availability by product version.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-27480. EPSS is 0.43%. Act only if a listed version of static web server is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-204. EPSS 0.43%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Feb 21, 2026 · NIST NVD
Detected
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 b
Jun 17, 2026 · NIST NVD
Updated
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 b
Sources
- CVE.orgVulnerability recordCVE-2026-27480
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-27480
30-day exploitation probability 0.4%
first.org - NIST NVDVulnerability recordCVE-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
nvd.nist.gov
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.