Deserialization in Langchain4j
CVE-2026-97869
A flaw has been found in langchain4j up to 1.5.3-beta10/1.11.10-beta18/1.18.1-beta27. This vulnerability affects the function AgenticScopeSerializer.fromJson of the file AgenticScopeJsonSerializationIT.java of the component LangChain4j-agentic. This manipulation causes deserialization. Remote exploitation of the attack is possible. The attack's complexity is rated as high. It is stated that the exploitability is difficult. The exploit has been published and may be used. Upgrading to version 1.5.3-beta11, 1.11.10-beta19 and 1.18.1-beta28 is able to resolve this issue. Upgrading the affected component is advised. The project maintainer kindly explains: "The issue was reported to us privately on 23 July 2026 and fixed in releases published on 29 July 2026. It is tracked as GHSA-gmwr-7wmf-mrjm. Exploitation requires an application to have enabled AgenticScope persistence, which is opt-in, and an attacker who can already write to that store. All maintained release lines have been patched."
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.1 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Langchain4j — versions 1.11.10-beta18, 1.18.1-beta27, 1.5.3-beta10
Weakness classification (CWE)
References
- vuldb.com/vuln/409886 (technical-description, vdb-entry)
- vuldb.com/vuln/409886/cti (signature, permissions-required)
- vuldb.com/cve/CVE-2026-97869 (third-party-advisory)
- vuldb.com/submit/911825 (third-party-advisory)
- github.com/langchain4j/langchain4j/security/advisories/GHSA-gmwr-7wmf-mrjm (related)
- github.com/afish3201-debug/CVE/blob/main/Insecure Jackson Default Typing Leads… (exploit)
- github.com/langchain4j/langchain4j/releases/tag/1.18.1 (patch)
- github.com/langchain4j/langchain4j/ (product)
Frequently asked questions
- What is CVE-2026-97869?
- CVE-2026-97869 is a medium-severity vulnerability in Langchain4j, classified under Improper Input Validation. CVSS score: 4.1/10. Published 2026-09-25.
- How severe is CVE-2026-97869?
- Medium severity. CVSS v3 base score is 4.1 out of 10.