CVE-2026-42554

{"id": "CVE-2026-42554", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-42554", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-05-15T18:24:24.733312Z"}}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 6.1, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 2.7, "exploitabilityScore": 2.8}], "cvssMetricV40": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 5.3, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/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": "PASSIVE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "LOW", "vulnIntegrityImpact": "NONE", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "LOW", "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"}}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "gofiber", "product": "fiber", "versions": [{"status": "affected", "version": "< 2.52.13"}, {"status": "affected", "version": ">= 3.0.0-beta.2, < 3.1.0"}]}]}], "published": "2026-05-11T23:19:48.083", "references": [{"url": "https://github.com/gofiber/fiber/security/advisories/GHSA-qjv7-627w-8qjv", "tags": ["Exploit", "Mitigation", "Vendor Advisory"], "source": "security-advisories@github.com"}, {"url": "https://github.com/gofiber/fiber/security/advisories/GHSA-qjv7-627w-8qjv", "tags": ["Exploit", "Mitigation", "Vendor Advisory"], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-79"}]}], "descriptions": [{"lang": "en", "value": "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 attacker-influenced data to the AutoFormat() feature. The developer opts into content negotiation by calling AutoFormat(), but does not opt into raw HTML emission for a particular request; Fiber chooses that branch from attacker-controlled Accept. The html branch is the sole outlier in a method whose name (AutoFormat) and symmetrical structure actively telegraph \"safe, format-agnostic reply.\" This vulnerability is fixed in 2.52.12 and 3.1.0."}, {"lang": "es", "value": "Fiber es un framework web para Go. Antes de 2.52.12 y 3.1.0, una vulnerabilidad de cross-site scripting en Go Fiber permite a un atacante remoto inyectar HTML/JavaScript arbitrario al proporcionar Accept: text/html en cualquier solicitud cuyo gestor pase datos influenciados por el atacante a la caracter\u00edstica AutoFormat(). El desarrollador opta por la negociaci\u00f3n de contenido al llamar a AutoFormat(), pero no opta por la emisi\u00f3n de HTML sin procesar para una solicitud particular; Fiber elige esa rama del Accept controlado por el atacante. La rama html es la \u00fanica excepci\u00f3n en un m\u00e9todo cuyo nombre (AutoFormat) y estructura sim\u00e9trica telegraf\u00edan activamente \u2019respuesta segura e independiente del formato.\u2019 Esta vulnerabilidad est\u00e1 corregida en 2.52.12 y 3.1.0."}], "lastModified": "2026-10-26T18:10:00.173", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:gofiber:fiber:*:*:*:*:*:go:*:*", "vulnerable": true, "matchCriteriaId": "599FC51E-5C0B-4F70-BDCA-5F08C7BA5F39", "versionEndExcluding": "2.52.12"}, {"criteria": "cpe:2.3:a:gofiber:fiber:*:*:*:*:*:go:*:*", "vulnerable": true, "matchCriteriaId": "0BE31D7D-3EA7-4474-930A-0FD4C237989C", "versionEndExcluding": "3.1.0", "versionStartIncluding": "3.0.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}