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Vulnerability record · CVE-2021-34371 · published 5 August 2021

CVE-2021-34371: Neo4j deserialization of untrusted data vulnerability

Neo4j · Neo4j

Neo4j through 3.4.18 (with the shell server enabled) exposes an RMI service that arbitrarily deserializes Java objects, e.g., through setSessionVariable. An attacker can abuse this for remote code execution because there are dependencies with exploitable gadget chains.

9.8 CVSS 3.1 Critical EPSS 13% · top 3.7% CWE-502 · Deserialization of untrusted data
9.8CVSS 3.1 base score, v2 7.5
13%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References, 2 tagged exploit
17 Jun 2026Last modified by NVD

Description

Neo4j through 3.4.18 (with the shell server enabled) exposes an RMI service that arbitrarily deserializes Java objects, e.g., through setSessionVariable. An attacker can abuse this for remote code execution because there are dependencies with exploitable gadget chains.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://www.exploit-db.com/exploits/50170 ExploitThird Party AdvisoryVDB Entry
https://www.exploit-db.com/exploits/50170 ExploitThird Party AdvisoryVDB Entry

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-34371), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.