High severity · published Feb 24, 2026
CVE-2026-25882
Fiber has a Denial of Service Vulnerability via Route Parameter Overflow
7.5
CVSS
0.7%
EPSS
No
On KEV
Description
Fiber is an Express inspired web framework written in Go. A denial of service vulnerability exists in Fiber v2 and v3 that allows remote attackers to crash the application by sending requests to routes with more than 30 parameters. The vulnerability results from missing validation during route registration combined with an unbounded array write during request matching. Version 2.52.12 patches the issue in the v2 branch and 3.1.0 patches the issue in the v3 branch.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 52% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FI
fiber · gofiber
>= 2.0.0, < 2.52.12; >= 3.0.0, < 3.1.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-25882
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-25882
Product
https://github.com/gofiber/fiber/blob/main/path.go#L514
Product
https://github.com/gofiber/fiber/blob/v2/path.go#L516
Issue Tracking
https://github.com/gofiber/fiber/pull/3962
Exploit
https://github.com/gofiber/fiber/security/advisories/GHSA-mrq8-rjmw-wpq3
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