PyPI/crossbar CVE-2026-77528: medium 5.3, EPSS 0.52%

Autobahn Python permessage-deflate bypasses maxMessagePayloadSize after inflation

Action: Upgrade crossbar to 26.7.1 or later.

pip install crossbar==26.7.1

Affected

Fixed versions

Sources

• osv: GHSA-hxp9-w8x3-p566#PyPI/crossbar
• https://github.com/crossbario/autobahn-python/security/advisories/GHSA-hxp9-w8x3-p566
• https://nvd.nist.gov/vuln/detail/CVE-2026-77528
• https://github.com/crossbario/autobahn-python/pull/1916
• https://github.com/crossbario/autobahn-python/commit/77d323a30b09b1828ad8be2ce6344e056970e613
• https://github.com/crossbario/autobahn-python
• https://github.com/crossbario/autobahn-python/releases/tag/v26_7_1

CVE-2026-77528 · published 2026-09-22T20:37:28Z · modified 2026-10-01T17:55:38.804385392Z · JSON