Unathenticated connection can hold Bolt channel open
Summary
| CVE | CVE-2026-14587 |
|---|---|
| State | PUBLISHED |
| Assigner | Neo4j |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-05 17:16:41 UTC |
| Updated | 2026-08-05 19:17:21 UTC |
| 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. |
Risk And Classification
Primary CVSS: v4.0 5.5 MEDIUM from 3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6
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
Problem Types: CWE-130 | CWE-130 CWE-130 Improper handling of length parameter inconsistency
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | 3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6 | Secondary | 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/C... |
| 4.0 | CNA | CVSS | 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 |
CVSS v4.0 Breakdown
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
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Neo4j | Enterprise Edition | affected 2025.01 2026.07 date | Not specified |
| CNA | Neo4j | Enterprise Edition | affected 5.0 5.26.29 semver | Not specified |
| CNA | Neo4j | Community Edition | affected 2025.01 2026.07 date | Not specified |
| CNA | Neo4j | Community Edition | affected 5.0 5.26.29 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| neo4j.com/security/CVE-2026-14587 | 3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6 | neo4j.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: [email protected] (Liyi), https://lzhou1110.github.io/ (en)
CNA: [email protected] (Ziyue), https://zyy0530.github.io/ (en)
CNA: [email protected] (Strick), https://str1ckl4nd.github.io/ (en)
CNA: [email protected] (Maurice), http://maurice.busystar.org/ (en)
CNA: [email protected] (Chenchen), https://7thparkk.github.io/ (en)