FKIE_CVE-2026-77528

Vulnerability from fkie_nvd - Published: 2026-09-18 20:17 - Updated: 2026-09-19 15:17
Severity
5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Summary
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.
References
security-advisories@github.comhttps://github.com/crossbario/autobahn-python/commit/77d323a30b09b1828ad8be2ce6344e056970e613
security-advisories@github.comhttps://github.com/crossbario/autobahn-python/pull/1916
security-advisories@github.comhttps://github.com/crossbario/autobahn-python/releases/tag/v26_7_1
security-advisories@github.comhttps://github.com/crossbario/autobahn-python/security/advisories/GHSA-hxp9-w8x3-p566
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "autobahn-python",
          "vendor": "crossbario",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 26.7.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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",
  "lastModified": "2026-09-19T15:17:02.063",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "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:L",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-77528",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-19T13:37:22.821549Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-18T20:17:22.830",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/crossbario/autobahn-python/commit/77d323a30b09b1828ad8be2ce6344e056970e613"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/crossbario/autobahn-python/pull/1916"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/crossbario/autobahn-python/releases/tag/v26_7_1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/crossbario/autobahn-python/security/advisories/GHSA-hxp9-w8x3-p566"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-409"
        },
        {
          "lang": "en",
          "value": "CWE-770"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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