What is CVE-2026-42554?

CVE-2026-42554 is a medium-severity vulnerability in Gofiber Fiber, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-05-11.

How severe is CVE-2026-42554?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Gofiber Fiber

CVE-2026-42554

Fiber is a web framework for Go. Prior to 2.52.12 and 3.1.0, Cross-Site Scripting vulnerability in Go Fiber allows a remote attacker to inject arbitrary HTML/JavaScript by supplying Accept: text/html on any request whose handler passes att…

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.000 (12.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Gofiber Fiber — versions < 2.52.13, >= 3.0.0-beta.2, < 3.1.0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)

Frequently asked questions

What is CVE-2026-42554?: CVE-2026-42554 is a medium-severity vulnerability in Gofiber Fiber, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-05-11.
How severe is CVE-2026-42554?: Medium severity. CVSS v3 base score is 6.1 out of 10.