Cyber Resilience

CVE-2026-25882

Gofiber Fiber 2.0.0 – 2.52.12

Public PoC
Published
24 February 2026
Modified
27 February 2026
Patch / advisory
View advisory
CVSS Score v4 5.5
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0059 45th percentile
Risk Priority 39 floored blend · peak EPSS

Summary

CVE-2026-25882 is a medium-severity Improper Validation of Array Index (CWE-129) vulnerability in Gofiber Fiber. Its CVSS base score is 5.5 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 45th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-25882 is a denial-of-service vulnerability in Fiber, an Express-inspired web framework written in Go, affecting versions v2 and v3 prior to the patched releases. The issue stems from missing validation during route registration combined with an unbounded array write operation during request matching, specifically triggered when processing routes with more than 30 parameters. This leads to application crashes and is classified under CWE-129 (Improper Validation of Array Index), with a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Remote attackers can exploit this vulnerability without authentication by sending crafted HTTP requests to any route endpoint that accepts parameters, provided the Fiber application exposes such routes over the network. Successful exploitation causes the server to crash due to the unbounded array write, resulting in a denial of service that disrupts availability for all users until the service is restarted. No privileges, user interaction, or special conditions are required beyond network access to the application.

Patches are available in Fiber version 2.52.12 for the v2 branch and version 3.1.0 for the v3 branch, which introduce proper validation to prevent the unbounded array writes. Security practitioners should upgrade to these versions immediately and review the GitHub security advisory (GHSA-mrq8-rjmw-wpq3) and associated pull request (#3962) for implementation details, including changes around path.go lines relevant to route parameter handling.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

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…

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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.

CWE(s)
CWE-129

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-48075Same product: Gofiber Fiber
CVE-2023-45128Same product: Gofiber Fiber
CVE-2026-25891Same product: Gofiber Fiber
CVE-2026-30246Same product: Gofiber Fiber
CVE-2026-42554Same product: Gofiber Fiber
CVE-2023-45141Same product: Gofiber Fiber
CVE-2024-25124Same product: Gofiber Fiber
CVE-2026-25899Same product: Gofiber Fiber
CVE-2024-38513Same product: Gofiber Fiber
CVE-2026-53624Same product: Gofiber Fiber

Affected Assets

gofiber
fiber
2.0.0 — 2.52.12 · 3.0.0 — 3.1.0

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input validation and bounds checking that prevent improper array indexing.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development can detect out-of-bounds array access but does not prevent the weakness by itself.

A.8.25 Secure development life cycle partial match
prevents

Secure development lifecycle mandates input validation and bounds checking that directly prevents improper array indexing.

A.8.26 Application security requirements partial match
prevents

Application security requirements include validation of untrusted input used for indexing or addressing memory structures.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles encourage defensive coding patterns that reduce index-related vulnerabilities.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly require bounds checking and validation of array indices derived from untrusted data.

References