CVE-2026-27480: Static Web Server (SWS) is a production-ready web server suitable for static web files or assets

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MEDIUM 5.3REMOTEUPGRADE

CVE-2026-27480 is a medium-severity flaw (CVSS 5.3) affecting static web server. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

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 userna

Why this priority

Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	5.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.4% (top 67%)
CISA exploited list	No
Weakness	CWE-204
Published	2026-02-21
Last modified	2026-06-17

Publisher (CNA): GitHub, Inc. · Vendor: static-web-server

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-02-21 10:16 UTCPublished CVE record published
2026-06-17 10:27 UTCUpdated Record last modified

static-web-server static web server UPGRADE

Affected: >= 2.1.0 and < 2.41.0

Fixed in: 2.41.0

Safe to downgrade to: a release before 2.1.0

1. Check installed version

apt-cache policy static-web-server || rpm -q static-web-server || static-web-server --version

2. UPGRADE to 2.41.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade static-web-server

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade static-web-server

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 2.1.0 (Debian / Ubuntu)

apt-cache madison static-web-server sudo apt install static-web-server=<VERSION_BEFORE_2.1.0> sudo apt-mark hold static-web-server

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list static-web-server sudo dnf downgrade static-web-server-<VERSION_BEFORE_2.1.0> sudo dnf versionlock add static-web-server

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-27480?

static web server: upgrade to 2.41.0. Exact commands for each OS are on this page.

Is CVE-2026-27480 being exploited?

CVE-2026-27480 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-27480 affect?

CVE-2026-27480 affects static web server. Severity is medium (CVSS 5.3). 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

How urgent is CVE-2026-27480?

Priority 37/100. Public exploit reference; Remotely exploitable, no login, no user action

Related CVEs

CVE-2025-67487 HIGH 8.6 UPGRADE Static Web Server (SWS) is a production-ready web server suitable for static web files or assets

References

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