{"identifier":"CVE-2026-116579","cve":{"id":"CVE-2026-116579","description":"Autobahn Python is a WebSocket and WAMP implementation for Python that supports Twisted and asyncio. From 26.7.1 until 26.10.1, PerMessageBrotli.decompress_message_data in compress_brotli.py calls the Brotli decompressor without an output limit and checks maxMessagePayloadSize only after a complete frame has been inflated. An unauthenticated WebSocket client can send a small, highly compressed frame that allocates hundreds of MiB before rejection, causing memory-exhaustion denial of service on servers that enable the opt-in permessage-brotli feature through the compress extra. Deflate and bzip2 already enforce the remaining output budget and are outside this residual vulnerability. This issue is fixed in version 26.10.1.","published":"2026-10-26T21:18:15.117000+00:00","modified":"2026-10-27T16:03:45.247000+00:00","status":"Awaiting Analysis","score":5.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","cvss_version":"3.1","affected":[],"weaknesses":["CWE-409","CWE-770"],"references":[{"url":"https://github.com/crossbario/autobahn-python/commit/a41442bbee4f6126a8ce1bb892840124c24d16f1","source":"security-advisories@github.com"},{"url":"https://github.com/crossbario/autobahn-python/pull/1987","source":"security-advisories@github.com"},{"url":"https://github.com/crossbario/autobahn-python/releases/tag/v26_10_1","source":"security-advisories@github.com"},{"url":"https://github.com/crossbario/autobahn-python/security/advisories/GHSA-pjh6-c8mg-3x7m","source":"security-advisories@github.com"}],"kev":null,"kev_checked":true,"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":5.9,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":2.2,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-10-27T13:41:50.957164Z","id":"CVE-2026-116579","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"configurations":[],"source":"nvd","retrieved_at":"2026-10-28T10:27:36.043320+00:00","exploited":false,"kev_stale":false,"products":[],"priority":{"label":"Assess exposure and vendor guidance","reasons":["No higher-priority signal is available in the current stored evidence."]},"epss":{"probability":0.00425,"percentile":0.36729,"date":"2026-10-29","stale":false},"version_assessment":null},"news":[],"campaigns":[],"domains":[{"domain":"github.com","source_url":"https://github.com/crossbario/autobahn-python/commit/a41442bbee4f6126a8ce1bb892840124c24d16f1","investigate_url":"https://investigate.aeglixmind.com/#github.com"}],"arsenal_url":"https://arsenal.aeglixmind.com/?cve=CVE-2026-116579","catalog_url":"https://cves.aeglixmind.com/cve/CVE-2026-116579","research_url":"https://investigate.aeglixmind.com/research/cve/CVE-2026-116579","coverage":{"news_candidates_checked":0,"campaign_candidates_checked":0,"bounded":false,"notice":"Exact CVE mentions in stored public excerpts and reviewed campaign content only. A mention is not proof of exploitation, attribution or tool suitability. Missing matches do not establish absence."}}