CVE-2026-1337: CVE-2026-1337: Insufficient escaping of unicode characters in query log in Neo4j Enterprise and Community…

CVE-2026-1337 at a glance

CVE-2026-1337 is a low-severity XSS vulnerability in Neo4j, with a CVSS 4.0 base score of 1.1. NVD published it on 2026-02-06 and classifies the weakness as CWE-117. Public exploit code: 3 public GitHub proof-of-concept repositories from 3 accounts, with the earliest exploit evidence dated 2026-02-06. FIRST EPSS puts the probability of exploitation activity in the next 30 days at 0.24% (percentile 15.8, scored 2026-11-03). NVD configuration data lists a fixed release for 1 product, for example neo4j neo4j 2026.01.0. Its CVERadar threat level is 10/100.

What it is

Insufficient escaping of unicode characters in query log in Neo4j Enterprise and Community editions prior to 2026.01 can lead to XSS if the user opens the logs in a tool that treats them as HTML. There is no security impact on Neo4j products, but this advisory is released as a precaution to treat the logs as plain text if using versions prior to 2026.01. Proof of concept exploit:  https://github.com/JoakimBulow/CVE-2026-1337

Exploitation evidence

First exploit evidence seen: 2026-02-06 (earliest date across the sources below).

Exploited in the wild

No source on this site lists in-the-wild exploitation yet (CISA KEV, VulnCheck KEV).

Public exploit code

GitHub proof-of-concept repositories

3 public repositories from 3 accounts, first seen 2026-02-06. Most starred: JoakimBulow/CVE-2026-1337 (5 stars), view the JoakimBulow/CVE-2026-1337 repository on GitHub.

Verify before running: public PoCs can be malicious. Read the code and only run it in an isolated lab. A PoC means exploit code is public, not that this CVE is exploited in the wild.

Sources: nomi-sec/PoC-in-GitHub.

Patches, mitigations and detection

Fixed versions

• neo4j neo4j: upgrade to 2026.01.0 or later

Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.

Vendor advisories and patches

No vendor-tagged reference yet; see the full reference list.

Detection Generic guidance

Response checklist Generic guidance

1. Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
2. Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
3. Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
4. Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.