CVE-2026-86318Public exploitNetwork attack vector

Service interruption via unbounded merge-patch recursion

Published Sep 7, 2026 · Updated Sep 8, 2026

Uncontrolled recursion in java-json-tools json-patch 1.0 through 1.13 allows remote attackers to interrupt service via deeply nested JSON. JsonMergePatchDeserializer recursively processes every nested object in JsonMergePatch.fromJson without enforcing a depth limit, causing StackOverflowError. Exposure requires an application to pass attacker-controlled JsonNode input to the merge-patch API; repeated failures can exhaust its processing threads.

CVSS severity5.3
Medium
EPSS probability0.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled recursion in java-json-tools json-patch 1.0 through 1.13 allows remote attackers to interrupt service via deeply nested JSON. JsonMergePatchDeserializer recursively processes every nested object in JsonMergePatch.fromJson without enforcing a depth limit, causing StackOverflowError. Exposure requires an application to pass attacker-controlled JsonNode input to the merge-patch API; repeated failures can exhaust its processing threads.

The record

CVE
CVE-2026-86318
Published
Sep 7, 2026
Updated
Sep 8, 2026
Vendor
Starcounter-Jack
Product
JSON-Patch
Classifications
CWE-119, CWE-121, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 7, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 8, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.0
  2. Affected versionversion=1.1
  3. Affected versionversion=1.10
  4. Affected versionversion=1.11
  5. Affected versionversion=1.12
  6. Affected versionversion=1.13
  7. Affected versionversion=1.2
  8. Affected versionversion=1.3
  9. Affected versionversion=1.4
  10. Affected versionversion=1.5
  11. Affected versionversion=1.6
  12. Affected versionversion=1.7
  13. Affected versionversion=1.8
  14. Affected versionversion=1.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Starcounter-Jack · JSON-Patchversion=1.0; version=1.1; version=1.10; version=1.11; version=1.12; version=1.13; version=1.2; version=1.3; version=1.4; version=1.5; version=1.6; version=1.7; version=1.8; version=1.9

Published CVSS scores

5.3VulDB CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5.0VulDB CNAAV:N/AC:L/Au:N/C:N/I:N/A:P
5.5VulDB CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-119Improper Restriction of Operations within the Bounds of a Memory Buffer
CWE-121Stack-based Buffer Overflow
T1499Endpoint Denial of Service

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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