CVE-2025-54801

Fiber is an Express inspired web framework written in Go. In versions 2.52.8 and below, when using Fiber's Ctx.BodyParser to parse form data containing a large numeric key that represents a slice index (e.g., test.18446744073704), the application crashes due to an out-of-bounds slice allocation in the underlying schema decoder. The root cause is that the decoder attempts to allocate a slice of length idx + 1 without validating whether the index is within a safe or reasonable range. If the idx is excessively large, this leads to an integer overflow or memory exhaustion, causing a panic or crash. This is fixed in version 2.52.9.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/gofiber/fiber/commit/e115c08b8f059a4a031b492aa9eef0712411853d	Patch
https://github.com/gofiber/fiber/security/advisories/GHSA-qx2q-88mx-vhg7	Vendor Advisory
https://github.com/gofiber/fiber/security/advisories/GHSA-qx2q-88mx-vhg7	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:gofiber:fiber:*:*:*:*:*:go:*:*

History

No history.

Information

Published : 2025-08-06 00:15

Updated : 2025-09-23 23:27

NVD link : CVE-2025-54801

Mitre link : CVE-2025-54801

CVE.ORG link : CVE-2025-54801

JSON object : View

Products Affected

gofiber

fiber

CWE

CWE-789

Memory Allocation with Excessive Size Value

{"id": "CVE-2025-54801", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "[email protected]", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}], "cvssMetricV40": [{"type": "Secondary", "source": "[email protected]", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 8.7, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "HIGH", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "published": "2025-08-06T00:15:31.033", "references": [{"url": "https://github.com/gofiber/fiber/commit/e115c08b8f059a4a031b492aa9eef0712411853d", "tags": ["Patch"], "source": "[email protected]"}, {"url": "https://github.com/gofiber/fiber/security/advisories/GHSA-qx2q-88mx-vhg7", "tags": ["Vendor Advisory"], "source": "[email protected]"}, {"url": "https://github.com/gofiber/fiber/security/advisories/GHSA-qx2q-88mx-vhg7", "tags": ["Vendor Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "[email protected]", "description": [{"lang": "en", "value": "CWE-789"}]}], "descriptions": [{"lang": "en", "value": "Fiber is an Express inspired web framework written in Go. In versions 2.52.8 and below, when using Fiber's Ctx.BodyParser to parse form data containing a large numeric key that represents a slice index (e.g., test.18446744073704), the application crashes due to an out-of-bounds slice allocation in the underlying schema decoder. The root cause is that the decoder attempts to allocate a slice of length idx + 1 without validating whether the index is within a safe or reasonable range. If the idx is excessively large, this leads to an integer overflow or memory exhaustion, causing a panic or crash. This is fixed in version 2.52.9."}, {"lang": "es", "value": "Fiber es un framework web inspirado en Express y escrito en Go. En las versiones 2.52.8 y anteriores, al usar Ctx.BodyParser de Fiber para analizar datos de formulario que contienen una clave num\u00e9rica grande que representa el \u00edndice de un segmento (p. ej., test.18446744073704), la aplicaci\u00f3n se bloquea debido a una asignaci\u00f3n de segmento fuera de los l\u00edmites en el decodificador de esquema subyacente. La causa principal es que el decodificador intenta asignar un segmento con una longitud de idx + 1 sin validar si el \u00edndice se encuentra dentro de un rango seguro o razonable. Si el idx es excesivamente grande, se produce un desbordamiento de enteros o un agotamiento de memoria, lo que provoca un p\u00e1nico o un bloqueo. Esto se solucion\u00f3 en la versi\u00f3n 2.52.9."}], "lastModified": "2025-09-23T23:27:27.047", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:gofiber:fiber:*:*:*:*:*:go:*:*", "vulnerable": true, "matchCriteriaId": "ABCB03A5-E695-43F0-B7B3-FC7C3D9B584F", "versionEndExcluding": "2.52.9"}], "operator": "OR"}]}], "sourceIdentifier": "[email protected]"}