CVE-2026-25891

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-25891", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-02-06T21:08:39.130Z", "datePublished": "2026-02-24T21:08:48.675Z", "dateUpdated": "2026-02-24T21:39:11.118Z"}, "containers": {"cna": {"title": "Fiber has an Arbitrary File Read in Static Middleware on Windows", "problemTypes": [{"descriptions": [{"cweId": "CWE-22", "lang": "en", "description": "CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')", "type": "CWE"}]}], "metrics": [{"cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 7.7, "baseSeverity": "HIGH", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P", "version": "4.0"}}], "references": [{"name": "https://github.com/gofiber/fiber/security/advisories/GHSA-m3c2-496v-cw3v", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/gofiber/fiber/security/advisories/GHSA-m3c2-496v-cw3v"}, {"name": "https://github.com/gofiber/fiber/pull/4064", "tags": ["x_refsource_MISC"], "url": "https://github.com/gofiber/fiber/pull/4064"}, {"name": "https://github.com/gofiber/fiber/commit/59133702301c2ab7b776dd123b474cbd995f2c86", "tags": ["x_refsource_MISC"], "url": "https://github.com/gofiber/fiber/commit/59133702301c2ab7b776dd123b474cbd995f2c86"}], "affected": [{"vendor": "gofiber", "product": "fiber", "versions": [{"version": ">= 3.0.0, < 3.1.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-02-24T21:08:48.675Z"}, "descriptions": [{"lang": "en", "value": "Fiber is an Express inspired web framework written in Go. A Path Traversal (CWE-22) vulnerability in Fiber allows a remote attacker to bypass the static middleware sanitizer and read arbitrary files on the server file system on Windows. This affects Fiber v3 through version 3.0.0. This has been patched in Fiber v3 version 3.1.0."}], "source": {"advisory": "GHSA-m3c2-496v-cw3v", "discovery": "UNKNOWN"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-02-24T21:39:00.083530Z", "id": "CVE-2026-25891", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-02-24T21:39:11.118Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-25891", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-02-24T21:39:00.083530Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-02-24T21:39:05.876Z"}}], "cna": {"title": "Fiber has an Arbitrary File Read in Static Middleware on Windows", "source": {"advisory": "GHSA-m3c2-496v-cw3v", "discovery": "UNKNOWN"}, "metrics": [{"cvssV4_0": {"version": "4.0", "baseScore": 7.7, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH"}}], "affected": [{"vendor": "gofiber", "product": "fiber", "versions": [{"status": "affected", "version": ">= 3.0.0, < 3.1.0"}]}], "references": [{"url": "https://github.com/gofiber/fiber/security/advisories/GHSA-m3c2-496v-cw3v", "name": "https://github.com/gofiber/fiber/security/advisories/GHSA-m3c2-496v-cw3v", "tags": ["x_refsource_CONFIRM"]}, {"url": "https://github.com/gofiber/fiber/pull/4064", "name": "https://github.com/gofiber/fiber/pull/4064", "tags": ["x_refsource_MISC"]}, {"url": "https://github.com/gofiber/fiber/commit/59133702301c2ab7b776dd123b474cbd995f2c86", "name": "https://github.com/gofiber/fiber/commit/59133702301c2ab7b776dd123b474cbd995f2c86", "tags": ["x_refsource_MISC"]}], "descriptions": [{"lang": "en", "value": "Fiber is an Express inspired web framework written in Go. A Path Traversal (CWE-22) vulnerability in Fiber allows a remote attacker to bypass the static middleware sanitizer and read arbitrary files on the server file system on Windows. This affects Fiber v3 through version 3.0.0. This has been patched in Fiber v3 version 3.1.0."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-22", "description": "CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-02-24T21:08:48.675Z"}}}, "cveMetadata": {"cveId": "CVE-2026-25891", "state": "PUBLISHED", "dateUpdated": "2026-02-24T21:39:11.118Z", "dateReserved": "2026-02-06T21:08:39.130Z", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "datePublished": "2026-02-24T21:08:48.675Z", "assignerShortName": "GitHub_M"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"product": "fiber", "vendor": "gofiber", "versions": [{"status": "affected", "version": ">= 3.0.0, < 3.1.0"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:gofiber:fiber:*:*:*:*:*:go:*:*", "matchCriteriaId": "0BE31D7D-3EA7-4474-930A-0FD4C237989C", "versionEndExcluding": "3.1.0", "versionStartIncluding": "3.0.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Fiber is an Express inspired web framework written in Go. A Path Traversal (CWE-22) vulnerability in Fiber allows a remote attacker to bypass the static middleware sanitizer and read arbitrary files on the server file system on Windows. This affects Fiber v3 through version 3.0.0. This has been patched in Fiber v3 version 3.1.0."}, {"lang": "es", "value": "Fiber es un framework web inspirado en Express escrito en Go. Una vulnerabilidad de salto de ruta (CWE-22) en Fiber permite a un atacante remoto eludir el saneador del middleware est\u00e1tico y leer archivos arbitrarios en el sistema de archivos del servidor en Windows. Esto afecta a Fiber v3 hasta la versi\u00f3n 3.0.0. Esto ha sido parcheado en Fiber v3 versi\u00f3n 3.1.0."}], "id": "CVE-2026-25891", "lastModified": "2026-06-17T10:25:23.377", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 7.7, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "PROOF_OF_CONCEPT", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/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", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-25891", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-02-24T21:39:00.083530Z", "version": "2.0.3"}}]}, "published": "2026-02-24T22:16:31.440", "references": [{"source": "security-advisories@github.com", "tags": ["Patch"], "url": "https://github.com/gofiber/fiber/commit/59133702301c2ab7b776dd123b474cbd995f2c86"}, {"source": "security-advisories@github.com", "tags": ["Exploit", "Issue Tracking"], "url": "https://github.com/gofiber/fiber/pull/4064"}, {"source": "security-advisories@github.com", "tags": ["Exploit", "Vendor Advisory"], "url": "https://github.com/gofiber/fiber/security/advisories/GHSA-m3c2-496v-cw3v"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-22"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[3.0.0,3.1.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "fiber", "source": "cna", "vendor": "gofiber"}, "product": "fiber", "vendor": "gofiber"}], "analysis": {"en": {"generated_at": "2026-04-18T10:52:17.628626+00:00", "value": {"mitigation_remediation": ["Upgrade to Fiber v3.1.0 or a later release that includes the fixed static middleware logic.", "If an upgrade is not immediately possible, disable or remove the static middleware that serves files on Windows or restrict its configuration to serve only from trusted directories.", "Apply network\u2011layer restrictions such as firewall rules or reverse proxy access controls to limit exposure of the static endpoint to trusted networks or IP ranges only."], "summary": {"action": "Patch Immediately", "impact": "Arbitrary File Read on Windows"}, "threat_synthesis": {"affected_systems": "The vulnerability exists in all Fiber releases from v3 up to and including v3.0.0. It has been resolved in Fiber v3.1.0. Users running the affected versions on Windows servers are at risk.", "description_and_impact": "Fiber implements an Express\u2011style static file middleware that is supposed to block path traversal. However, a flaw in the sanitizer allows a remote attacker to craft a request that escapes the intended directory, enabling reads of any file on the server\u2019s file system. The flaw maps to CWE\u201122 and compromises confidentiality by exposing sensitive data, configuration files, or credentials without authentication.", "risk_and_exploitability": "The CVSS score of 7.7 indicates a high severity, while the EPSS score of less than 1% suggests that exploitation attempts are currently very rare. The issue is not listed in CISA\u2019s KEV catalog. Attackers can exploit it remotely through a crafted HTTP request to the static middleware endpoint, bypassing the intended sanitization logic. No additional user interaction or privileged access is required."}}}}, "created": "2026-02-25T11:35:30.622239+00:00", "updated": "2026-04-18T11:00:05.740289+00:00", "vendors": ["gofiber", "gofiber$PRODUCT$fiber"]}