{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "ESPAsyncWebServer",
          "vendor": "ESP32Async",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.11.2"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "ESPAsyncWebServer is an asynchronous HTTP and WebSocket server library for ESP32, ESP8266, RP2040 and RP2350. Prior to version 3.11.2, the multipart parser in `src/WebRequest.cpp` frees `_itemBuffer` and sets it to NULL when `BOUNDARY_OR_DATA` matches the closing boundary of a file part, before confirming the following terminator, while leaving `_itemIsFile` true. If the next byte is neither the final closing dashes nor a clean CRLF, the `DASH3_OR_RETURN2` or `EXPECT_FEED2` rewind branch re-injects provisionally consumed bytes through `itemWriteByte`. Because `_itemIsFile` remains true, `_itemBuffer`[`_itemBufferIndex`++] writes through a null pointer. On ESP32 this causes a `StoreProhibited` exception, panic and device reboot, producing remote denial of service. A route with a non-trivial body/upload handler, such as a file-upload or web-OTA endpoint, must be present. This issue is fixed in version 3.11.2."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-476",
              "description": "CWE-476: NULL Pointer Dereference",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-672",
              "description": "CWE-672: Operation on a Resource after Expiration or Release",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-30T20:53:37.292Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/ESP32Async/ESPAsyncWebServer/security/advisories/GHSA-8m8p-vhxc-jmjw",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/ESP32Async/ESPAsyncWebServer/security/advisories/GHSA-8m8p-vhxc-jmjw"
        },
        {
          "name": "https://github.com/ESP32Async/ESPAsyncWebServer/commit/4efbd35e597d91f01749f2d4a14bb78fba8ea02e",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/ESP32Async/ESPAsyncWebServer/commit/4efbd35e597d91f01749f2d4a14bb78fba8ea02e"
        },
        {
          "name": "https://github.com/ESP32Async/ESPAsyncWebServer/tree/v3.11.2",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/ESP32Async/ESPAsyncWebServer/tree/v3.11.2"
        }
      ],
      "source": {
        "advisory": "GHSA-8m8p-vhxc-jmjw",
        "discovery": "UNKNOWN"
      },
      "title": "ESPAsyncWebServer multipart parser has null-pointer write"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-62966",
    "datePublished": "2026-10-30T20:53:37.292Z",
    "dateReserved": "2026-07-14T22:48:09.779Z",
    "dateUpdated": "2026-10-30T20:53:37.292Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}