CVE-2026-14587
Unathenticated connection can hold Bolt channel open
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.
INFO
Published Date :
Aug. 5, 2026, 5:16 p.m.
Last Modified :
Aug. 5, 2026, 5:16 p.m.
Remotely Exploit :
Yes !
Source :
3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6
Affected Products
The following products are affected by CVE-2026-14587
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | MEDIUM | 3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6 | ||||
| CVSS 4.0 | MEDIUM | 3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6 |
Solution
- Apply Neo4j updates or patches.
- Ensure proper handling of handshake messages.
- Monitor Bolt connector activity.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-14587.
| URL | Resource |
|---|---|
| https://neo4j.com/security/CVE-2026-14587 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-14587 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-14587
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-14587 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-14587 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 3b236295-4ccd-4a1f-a1c1-a72eecc8d7b6
Aug. 05, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'neo4j', 'product': 'Enterprise Edition', 'versions': [{'status': 'affected', 'version': '2025.01', 'lessThan': '2026.07', 'versionType': 'date'}, {'status': 'affected', 'version': '5.0', 'lessThan': '5.26.29', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}, {'repo': 'https://github.com/neo4j/neo4j', 'vendor': 'neo4j', 'product': 'Community Edition', 'versions': [{'status': 'affected', 'version': '2025.01', 'lessThan': '2026.07', 'versionType': 'date'}, {'status': 'affected', 'version': '5.0', 'lessThan': '5.26.29', 'versionType': 'semver'}], 'packageName': 'neo4j', 'collectionURL': 'https://mvnrepository.com/artifact/org.neo4j/', 'defaultStatus': 'unaffected'}] Added 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. Added CVSS V4.0 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 Added CWE CWE-130 Added Reference https://neo4j.com/security/CVE-2026-14587