{"id":"CVE-2026-77528","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-77528","generatedAt":"2026-10-28T01:19:32.036Z","title":"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.","description":"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.","published":"2026-09-18T20:17:23.000Z","lastModified":"2026-09-24T21:25:27.000Z","status":"Deferred","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"cwe":["CWE-409","CWE-770"],"affected":[],"epss":{"score":0.00524,"percentile":0.44163,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.52%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"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","source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-77528","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}