{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-54571", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-06-15T19:15:27.343Z", "datePublished": "2026-09-17T18:28:26.977Z", "dateUpdated": "2026-09-17T18:28:26.977Z"}, "containers": {"cna": {"title": "ESPAsyncWebServer: Integer overflow in multipart boundary parser causes denial of service", "problemTypes": [{"descriptions": [{"cweId": "CWE-190", "lang": "en", "description": "CWE-190: Integer Overflow or Wraparound", "type": "CWE"}]}], "metrics": [{"cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 8.7, "baseSeverity": "HIGH", "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", "version": "4.0"}}], "references": [{"name": "https://github.com/ESP32Async/ESPAsyncWebServer/security/advisories/GHSA-4phx-fcj6-46r4", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/ESP32Async/ESPAsyncWebServer/security/advisories/GHSA-4phx-fcj6-46r4"}, {"name": "https://github.com/ESP32Async/ESPAsyncWebServer/pull/445", "tags": ["x_refsource_MISC"], "url": "https://github.com/ESP32Async/ESPAsyncWebServer/pull/445"}, {"name": "https://github.com/ESP32Async/ESPAsyncWebServer/commit/b928de7cbd7debcd6266ece6a6c46f10a86d3a6f", "tags": ["x_refsource_MISC"], "url": "https://github.com/ESP32Async/ESPAsyncWebServer/commit/b928de7cbd7debcd6266ece6a6c46f10a86d3a6f"}, {"name": "https://github.com/ESP32Async/ESPAsyncWebServer/releases/tag/v3.11.1", "tags": ["x_refsource_MISC"], "url": "https://github.com/ESP32Async/ESPAsyncWebServer/releases/tag/v3.11.1"}], "affected": [{"vendor": "ESP32Async", "product": "ESPAsyncWebServer", "versions": [{"version": "< 3.11.1", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-09-17T18:28:26.977Z"}, "descriptions": [{"lang": "en", "value": "ESPAsyncWebServer is an asynchronous HTTP and WebSocket server library for ESP32, ESP8266, RP2040 and RP2350. Prior to 3.11.1, the multipart/form-data parser in src/WebRequest.cpp stores _boundaryPosition as an 8-bit value while _parseMultipartPostByte processes the boundary. A remote request containing an exactly 256-byte multipart boundary wraps _boundaryPosition from 255 to zero, prevents the boundary parsing loop from terminating, consumes excessive CPU, and triggers a FreeRTOS watchdog reset on affected ESP32 or ESP8266 devices. This issue is fixed in version 3.11.1."}], "source": {"advisory": "GHSA-4phx-fcj6-46r4", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "ESPAsyncWebServer", "vendor": "ESP32Async", "versions": [{"status": "affected", "version": "< 3.11.1"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "ESPAsyncWebServer is an asynchronous HTTP and WebSocket server library for ESP32, ESP8266, RP2040 and RP2350. Prior to 3.11.1, the multipart/form-data parser in src/WebRequest.cpp stores _boundaryPosition as an 8-bit value while _parseMultipartPostByte processes the boundary. A remote request containing an exactly 256-byte multipart boundary wraps _boundaryPosition from 255 to zero, prevents the boundary parsing loop from terminating, consumes excessive CPU, and triggers a FreeRTOS watchdog reset on affected ESP32 or ESP8266 devices. This issue is fixed in version 3.11.1."}], "id": "CVE-2026-54571", "lastModified": "2026-09-17T19:16:50.843", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 8.7, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "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: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", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-09-17T19:16:50.843", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/ESP32Async/ESPAsyncWebServer/commit/b928de7cbd7debcd6266ece6a6c46f10a86d3a6f"}, {"source": "security-advisories@github.com", "url": "https://github.com/ESP32Async/ESPAsyncWebServer/pull/445"}, {"source": "security-advisories@github.com", "url": "https://github.com/ESP32Async/ESPAsyncWebServer/releases/tag/v3.11.1"}, {"source": "security-advisories@github.com", "url": "https://github.com/ESP32Async/ESPAsyncWebServer/security/advisories/GHSA-4phx-fcj6-46r4"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-190"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}