{
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09"
      },
      "title": "HPACK encoder desynchronizes from the decoder after a failed header encode",
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-696 Incorrect Behavior Order",
              "lang": "en",
              "cweId": "CWE-696",
              "type": "CWE"
            }
          ]
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "affected": [
        {
          "vendor": "Apache Software Foundation",
          "product": "Apache Traffic Server",
          "versions": [
            {
              "status": "affected",
              "version": "8.0.0",
              "lessThanOrEqual": "8.1.9",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "9.0.0",
              "lessThanOrEqual": "9.2.14",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "10.0.0",
              "lessThanOrEqual": "10.1.3",
              "versionType": "semver"
            }
          ],
          "defaultStatus": "unaffected"
        }
      ],
      "descriptions": [
        {
          "value": "Apache Traffic Server updates the HTTP/2 HPACK dynamic table before confirming the header block encoded successfully, so an encode failure leaves the encoder out of sync with the peer decoder and corrupts subsequent header blocks on the connection.\n\nThis issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3.\n\nUsers are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.",
          "lang": "en",
          "supportingMedia": [
            {
              "type": "text/html",
              "base64": false,
              "value": "<p>Apache Traffic Server updates the HTTP/2 HPACK dynamic table before confirming the header block encoded successfully, so an encode failure leaves the encoder out of sync with the peer decoder and corrupts subsequent header blocks on the connection.</p><p>This issue affects Apache Traffic Server: from 8.0.0 through 8.1.9, from 9.0.0 through 9.2.14, from 10.0.0 through 10.1.3.</p><p>Users are recommended to upgrade to version 9.2.15 or 10.1.4, which fix the issue.</p>"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://lists.apache.org/thread/5prl9glcm9g2swnq9hqxvnokylm1gr6d",
          "tags": [
            "vendor-advisory"
          ]
        }
      ],
      "metrics": [
        {
          "other": {
            "type": "Textual description of severity",
            "content": {
              "text": "moderate"
            }
          }
        },
        {
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ],
          "cvssV3_1": {
            "version": "3.1",
            "attackVector": "NETWORK",
            "attackComplexity": "HIGH",
            "privilegesRequired": "NONE",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "availabilityImpact": "LOW",
            "baseSeverity": "MEDIUM",
            "baseScore": 4.8,
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L"
          }
        },
        {
          "format": "CVSS",
          "scenarios": [
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              "lang": "en",
              "value": "GENERAL"
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          "cvssV4_0": {
            "version": "4.0",
            "attackVector": "NETWORK",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "privilegesRequired": "NONE",
            "userInteraction": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "subIntegrityImpact": "LOW",
            "vulnAvailabilityImpact": "NONE",
            "subAvailabilityImpact": "NONE",
            "Safety": "NOT_DEFINED",
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "valueDensity": "NOT_DEFINED",
            "vulnerabilityResponseEffort": "NOT_DEFINED",
            "providerUrgency": "NOT_DEFINED",
            "baseSeverity": "MEDIUM",
            "baseScore": 6.3,
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N"
          }
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Omkhar Arasaratnam",
          "type": "reporter"
        },
        {
          "lang": "en",
          "value": "Apache Community",
          "type": "reporter"
        }
      ],
      "x_generator": {
        "engine": "scripts/cve_render.py"
      }
    }
  },
  "cveMetadata": {
    "cveId": "CVE-2026-65100",
    "assignerOrgId": "f0158376-9dc2-43b6-827c-5f631a4d8d09",
    "serial": 1,
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}