# CVE-2026-67215: cJSON JSON Patch copy/add Uncontrolled Recursion Stack Exhaustion

> An attacker can crash the application by supplying a malicious JSON Patch that causes uncontrolled recursion and stack exhaustion in the cJSON library.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 29 Jul 2026
- **Updated:** 29 Jul 2026
- **Also known as:** AZL-94410, AZL-94437, DEBIAN-CVE-2026-67215, ECHO-29ef-6520-8114, GHSA-5q3m-r3x7-8phg, ROOT-OS-ALPINE-321-CVE-2026-67215, ROOT-OS-ALPINE-323-CVE-2026-67215, UBUNTU-CVE-2026-67215

## What is CVE-2026-67215?

CVE-2026-67215 is a high-severity denial of service vulnerability in DaveGamble cJSON, published on 29 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

cJSON through 1.7.19 is vulnerable to uncontrolled recursion leading to stack exhaustion when an untrusted RFC 6902 JSON Patch is applied via cJSONUtils_ApplyPatches() or cJSONUtils_ApplyPatchesCaseSensitive(). A patch containing add and copy operations grafts duplicated subtrees to amplify document depth beyond the parser's nesting limit: cJSON_Delete() recurses with no depth bound, and the cJSON_Duplicate() guard CJSON_CIRCULAR_LIMIT is set to 10000, ten times the parser's 1000-level nesting limit and high enough to overflow a default thread stack. An attacker who can supply the patch document can crash the process, resulting in denial of service.

Weakness: CWE-674 (Uncontrolled Recursion)

## Which versions are affected by CVE-2026-67215?

It affects 1 product.


Products: Davegamble Cjson.

## How do I fix CVE-2026-67215?

Upgrade to a fixed version.

## Is CVE-2026-67215 being exploited?

There is no known exploitation of CVE-2026-67215 in the wild and no public exploit code.

## Other vulnerabilities in DaveGamble cJSON

- [CVE-2025-57052](https://insights.sbomify.com/CVE-2025-57052/): Memory corruption in n/a (critical 9.8)
- [CVE-2019-11834](https://insights.sbomify.com/CVE-2019-11834/): Memory corruption in n/a (critical 9.8)
- [CVE-2019-11835](https://insights.sbomify.com/CVE-2019-11835/): Memory corruption in n/a (critical 9.8)
- [CVE-2016-10749](https://insights.sbomify.com/CVE-2016-10749/): Memory corruption in n/a (critical 9.8)
- [CVE-2018-1000217](https://insights.sbomify.com/CVE-2018-1000217/): Use after free in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-67215 and fix it if it is affected.

What it is: CVE-2026-67215 is a high-severity denial of service vulnerability in DaveGamble cJSON, published on 29 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-67215 in the wild and no public exploit code.

Affected product: DaveGamble cJSON. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-67215/ (Markdown: https://insights.sbomify.com/CVE-2026-67215/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-67215
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-67215
- OSV: https://osv.dev/vulnerability/CVE-2026-67215

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-67215/
Summaries are generated and may contain mistakes; the official description above is the record.