CVE-2026-14587 Neo4j
| Affected software | Neo4j |
|---|---|
| Severity | 5.5 Medium CVSS 4.0 2 scores |
| Weakness | CWE-130 |
| Published | 5 Aug 2026 |
| Updated | 28 Aug 2026 |
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.
Exploitation status
No public exploit
No exploit has been reported in the sources we check.
Exploitation status
- CISA KEV not listed
- VulnCheck KEV not listed
- CISA Vulnrichment exploitation: none
- Indexed PoC none indexed
- EPSS 0.54% chance in 30 days
Waratek protection
Within Waratek scope. In the sources we check, nobody has published exploit code for this CVE or reported it being exploited.
VRT has not found a public code change for this CVE yet.
- Protection none
- Action not pursued
- Review automated Upstream data
- Record active
| Decided by | Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read |
|---|---|
| Finding | This CVE affects a known product, but nothing published names a fix and nothing published shows an exploit. That is a statement about the evidence, not about the defect — it does not mean the vulnerability is unimportant or unreachable, only that neither of the two things VRT can act on exists. |
CVSS
5.5 MEDIUM
v4.0 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
2 metrics
CVSS
5.5 MEDIUM v4.0CVSS: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
2 metrics
We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.
| Version | Score | Band | Vector | Assigner | Type | |
|---|---|---|---|---|---|---|
| CVSS 4.0 | 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 |
Neo4j | Secondary | published |
| CVSS 3.1 | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
NVD | Primary |
Affected software and releases
Products and versions
1 product, 2 version entries| Source | Vendor | Product | Scheme | Affected versions |
|---|---|---|---|---|
| nvd | neo4j | neo4j | generic | ≥ 5.0.0 and < 5.26.29 · ≥ 2025.1.0 and < 2026.7.0 |
References
| URL | Tags |
|---|---|
| https://neo4j.com/security/CVE-2026-14587 | Vendor Advisory |
Timeline
Timeline
| Published | 2026-08-05 | By the CVE Program. |
|---|---|---|
| NVD record modified | 2026-08-28 | NVD's own last-modified date for this record. |