{"items":[{"id":"NVI-00012990","kind":"vulnerability","title":"Autobahn Python permessage-deflate bypasses maxMessagePayloadSize after inflation","revision":2,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-hxp9-w8x3-p566","CVE-2026-77528"],"plain_summary":"GitHub lists this reviewed advisory for autobahn, crossbar. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-41e6828a893f298bddbf3bc2cbd1194f"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-09-22T20:37:28.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-316d3827c656fb67eb72e82303386068"},{"kind":"EPSS","as_of":"2026-11-01T12:00:16.000Z","value":"0.524%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.44435. Missing scores are unknown.","source_id":"sr-41e6828a893f298bddbf3bc2cbd1194f"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-316d3827c656fb67eb72e82303386068","url":"https://github.com/advisories/GHSA-hxp9-w8x3-p566","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-hxp9-w8x3-p566","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T07:25:10.521Z"},{"id":"sr-41e6828a893f298bddbf3bc2cbd1194f","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-77528","publisher":"FIRST EPSS","observed_at":"2026-11-01T14:28:32.287Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-316d3827c656fb67eb72e82303386068"],"technology":"autobahn","known_exclusions":[],"conditions_summary":"### Summary\nAutobahn Python enforces `maxMessagePayloadSize` against the compressed WebSocket frame length before permessage-deflate inflation, then delivers the inflated message to application callbacks without a second size check. A client frame that is only 22 compressed bytes can inflate to 4096 bytes and reach `onMessage` even when the application configured a 128-byte message limit, defeating the resource boundary the option is meant to provide.\n\n### Details\nThe permessage-deflate path installs a `PerMessageDeflate` instance when the server accepts a client offer in `src/autobahn/websocket/protocol.py:3371`. The common `PerMessageDeflateOfferAccept(offer)` path leaves `max_message_size` at its default `None` in `src/autobahn/websocket/compress_deflate.py:295`, and that value is copied into the compressor object in `src/autobahn/websocket/compress_deflate.py:723`. When a data frame arrives with RSV1 set, Autobahn marks the message compressed in `src/autobahn/websocket/protocol.py:1812`, calls `onMessageFrameBegin` with the compressed frame length, and increments `message_data_total_length` by that pre-inflate length in `src/autobahn/websocket/protocol.py:634`; the configured m","public_affected_ranges":["< 26.7.1"]},{"certainty":"source_listed","source_ids":["sr-316d3827c656fb67eb72e82303386068"],"technology":"crossbar","known_exclusions":[],"conditions_summary":"### Summary\nAutobahn Python enforces `maxMessagePayloadSize` against the compressed WebSocket frame length before permessage-deflate inflation, then delivers the inflated message to application callbacks without a second size check. A client frame that is only 22 compressed bytes can inflate to 4096 bytes and reach `onMessage` even when the application configured a 128-byte message limit, defeating the resource boundary the option is meant to provide.\n\n### Details\nThe permessage-deflate path installs a `PerMessageDeflate` instance when the server accepts a client offer in `src/autobahn/websocket/protocol.py:3371`. The common `PerMessageDeflateOfferAccept(offer)` path leaves `max_message_size` at its default `None` in `src/autobahn/websocket/compress_deflate.py:295`, and that value is copied into the compressor object in `src/autobahn/websocket/compress_deflate.py:723`. When a data frame arrives with RSV1 set, Autobahn marks the message compressed in `src/autobahn/websocket/protocol.py:1812`, calls `onMessageFrameBegin` with the compressed frame length, and increments `message_data_total_length` by that pre-inflate length in `src/autobahn/websocket/protocol.py:634`; the configured m","public_affected_ranges":["< 26.7.1"]}],"null_published_at":"2026-11-08T19:53:48.777Z","source_updated_at":"2026-09-22T20:37:28.000Z","source_disclosed_at":"2026-09-22T20:37:28.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-11-01T07:25:10.521Z"},{"id":"NVI-00012990","kind":"vulnerability","title":"Autobahn Python permessage-deflate bypasses maxMessagePayloadSize after inflation","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-hxp9-w8x3-p566","CVE-2026-77528"],"plain_summary":"GitHub lists this reviewed advisory for autobahn, crossbar. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-316d3827c656fb67eb72e82303386068"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-09-22T20:37:28.000Z","value":"5.3 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-316d3827c656fb67eb72e82303386068"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-316d3827c656fb67eb72e82303386068","url":"https://github.com/advisories/GHSA-hxp9-w8x3-p566","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-hxp9-w8x3-p566","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T07:25:10.521Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-316d3827c656fb67eb72e82303386068"],"technology":"autobahn","known_exclusions":[],"conditions_summary":"### Summary\nAutobahn Python enforces `maxMessagePayloadSize` against the compressed WebSocket frame length before permessage-deflate inflation, then delivers the inflated message to application callbacks without a second size check. A client frame that is only 22 compressed bytes can inflate to 4096 bytes and reach `onMessage` even when the application configured a 128-byte message limit, defeating the resource boundary the option is meant to provide.\n\n### Details\nThe permessage-deflate path installs a `PerMessageDeflate` instance when the server accepts a client offer in `src/autobahn/websocket/protocol.py:3371`. The common `PerMessageDeflateOfferAccept(offer)` path leaves `max_message_size` at its default `None` in `src/autobahn/websocket/compress_deflate.py:295`, and that value is copied into the compressor object in `src/autobahn/websocket/compress_deflate.py:723`. When a data frame arrives with RSV1 set, Autobahn marks the message compressed in `src/autobahn/websocket/protocol.py:1812`, calls `onMessageFrameBegin` with the compressed frame length, and increments `message_data_total_length` by that pre-inflate length in `src/autobahn/websocket/protocol.py:634`; the configured m","public_affected_ranges":["< 26.7.1"]},{"certainty":"source_listed","source_ids":["sr-316d3827c656fb67eb72e82303386068"],"technology":"crossbar","known_exclusions":[],"conditions_summary":"### Summary\nAutobahn Python enforces `maxMessagePayloadSize` against the compressed WebSocket frame length before permessage-deflate inflation, then delivers the inflated message to application callbacks without a second size check. A client frame that is only 22 compressed bytes can inflate to 4096 bytes and reach `onMessage` even when the application configured a 128-byte message limit, defeating the resource boundary the option is meant to provide.\n\n### Details\nThe permessage-deflate path installs a `PerMessageDeflate` instance when the server accepts a client offer in `src/autobahn/websocket/protocol.py:3371`. The common `PerMessageDeflateOfferAccept(offer)` path leaves `max_message_size` at its default `None` in `src/autobahn/websocket/compress_deflate.py:295`, and that value is copied into the compressor object in `src/autobahn/websocket/compress_deflate.py:723`. When a data frame arrives with RSV1 set, Autobahn marks the message compressed in `src/autobahn/websocket/protocol.py:1812`, calls `onMessageFrameBegin` with the compressed frame length, and increments `message_data_total_length` by that pre-inflate length in `src/autobahn/websocket/protocol.py:634`; the configured m","public_affected_ranges":["< 26.7.1"]}],"null_published_at":"2026-11-01T07:29:12.907Z","source_updated_at":"2026-09-22T20:37:28.000Z","source_disclosed_at":"2026-09-22T20:37:28.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-01T07:25:10.521Z"}],"next_cursor":null,"snapshot_revision":"42594"}