Enterprise Edition
Monthly
Bolt protocol handshake decoder in Neo4j Enterprise and Community Editions fails to distinguish overlong capability masks from truncated ones, leaving server-side channels permanently open without producing a finalization message. Any unauthenticated client reaching the Bolt connector (default TCP 7687) can trigger this pre-authentication stall by sending 32 continuation bytes in the capability mask, causing the decoder to loop on the same unread bytes. The CVSS 4.0 vector carries E:P (proof of concept exists) with a low availability impact; no active exploitation has been confirmed via CISA KEV, but the trivial pre-auth trigger and POC availability increase realistic risk to exposed Bolt endpoints.
Bolt protocol handshake decoder in Neo4j Enterprise and Community Editions fails to distinguish overlong capability masks from truncated ones, leaving server-side channels permanently open without producing a finalization message. Any unauthenticated client reaching the Bolt connector (default TCP 7687) can trigger this pre-authentication stall by sending 32 continuation bytes in the capability mask, causing the decoder to loop on the same unread bytes. The CVSS 4.0 vector carries E:P (proof of concept exists) with a low availability impact; no active exploitation has been confirmed via CISA KEV, but the trivial pre-auth trigger and POC availability increase realistic risk to exposed Bolt endpoints.