CVEvulnerability

CVE-2026-14587

5.5 MEDIUM Published 2026-08-05 Modified 2026-08-28 Official page ↗
Status
Analyzed
Published
2026-08-05
Last modified
2026-08-28
Assigner
3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6
CVSS 4.0 (3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6)
5.5 MEDIUM — CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS 3.1 ([email protected])
7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weaknesses
CWE-130

Description

Neo4j's Bolt modern handshake decoder treats an overlong capability bit mask the same way it treats a truncated bit mask. When an unauthenticated client sends a selected protocol version followed by 32 continuation bytes in the capability mask, the decoder resets the reader index and waits for more bytes instead of rejecting the protocol message and closing the channel. Because the same unread bytes remain at the front of the decoder buffer, appending a terminating byte later does not recover the connection. The decoder re-reads the same first 32 continuation bytes, returns without producing a handshake-finalization message, and leaves the channel open. This can be triggered before authentication by any client that can reach the Bolt connector.

Affected configurations

• neo4j neo4j (>= 5.0.0 < 5.26.29) • neo4j neo4j (>= 2025.01.0 < 2026.07.0)

Related

Weakness · CWE (1)

  • CWE-130 Improper Handling of Length Parameter Inconsistency weakness

References