{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "26.7.1"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "77d323a30b09b1828ad8be2ce6344e056970e613"
            },
            {
              "fixed": "22055b5a3b0e92307e348010260d775dec05be8c"
            }
          ],
          "repo": "https://github.com/crossbario/autobahn-python",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-hxp9-w8x3-p566"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-409",
      "CWE-770"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77528.json"
  },
  "details": "Autobahn Python is a WebSocket and WAMP implementation for Python that supports Twisted and asyncio. Prior to 26.7.1, WebSocket endpoints that accept permessage-deflate and rely on maxMessagePayloadSize enforce that limit against the compressed frame length before inflation but do not recheck the decompressed message size before delivery. A remote unauthenticated client can send a valid compressed frame below the configured wire-size limit that expands beyond the application message limit, causing oversized data to be allocated, joined, validated, and passed to application callbacks. This can create resource-exhaustion pressure, but the advisory does not establish confidentiality or integrity impact. This issue is fixed in version 26.7.1.",
  "id": "CVE-2026-77528",
  "modified": "2026-09-20T11:30:50.735447542Z",
  "published": "2026-09-18T19:42:18.767Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/crossbario/autobahn-python/releases/tag/v26_7_1"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77528.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/crossbario/autobahn-python/security/advisories/GHSA-hxp9-w8x3-p566"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-77528"
    },
    {
      "type": "FIX",
      "url": "https://github.com/crossbario/autobahn-python/commit/77d323a30b09b1828ad8be2ce6344e056970e613"
    },
    {
      "type": "FIX",
      "url": "https://github.com/crossbario/autobahn-python/pull/1916"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Autobahn Python permessage-deflate bypasses maxMessagePayloadSize after inflation"
}