Vulnerability · Published Sep 7, 2026 · Assigned by VulDB

CVE-2026-86318java-json-tools json-patch JsonMergePatchDeserializer.java JsonMergePatch.fromJson stack-based overflow

Medium 5.3

In plain English

A medium-severity stack buffer overflow in json-patch from java-json-tools. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 55% of all known vulnerabilities).

Severity (CVSS 3.1)5.3Medium

Exploit odds (30 days)0.8%top 44.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

A flaw has been found in java-json-tools json-patch up to 1.13. Affected is the function JsonMergePatch.fromJson of the file JsonMergePatchDeserializer.java. Executing a manipulation can lead to stack-based buffer overflow. The attack may be performed from remote. The exploit has been published and may be used. The project was informed of the problem early through an issue report but has not responded yet.

Affected products (as reported)

Vendor	Product	Versions
java-json-tools	json-patch	1.01.11.21.31.41.51.61.7

Weakness: CWE-121, CWE-119 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R

References

VDB-399509 | java-json-tools json-patch JsonMergePatchDeserializer.java JsonMergePatch.fromJson stack-based overflow vdb-entry, technical-description
VDB-399509 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
CVE-2026-86318 | CVE Analysis and Report third-party-advisory
Submit #908319 | java-json-tools json-patch 1.13 Stack Overflow DoS via Uncontrolled Recursion third-party-advisory
https://github.com/java-json-tools/json-patch/issues/168 exploit, issue-tracking, patch
https://github.com/java-json-tools/json-patch/ patch, product