PT-2026-65813 · Dave Gamble · Cjson

CVE-2026-67215 · Published 2026-07-29 · Updated 2026-07-29

NVD

CVSS v3.1

7.5

High

Base vector

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

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.

Exploit

Fix

Uncontrolled Recursion

Weakness Enumeration

CWE-674

Related Identifiers

CVE-2026-67215

Affected Products

Cjson

References · 5

• 🔥 https://joshua.hu/cjson-json-parser-cve-vulnerabilities · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2026-67215 · Security Note
• https://vulncheck.com/advisories/cjson-json-patch-copy-add-uncontrolled-recursion-stack-exhaustion · Note
• https://github.com/DaveGamble/cJSON/blob/v1.7.19/cJSON_Utils.c#L906-L940 · Note
• https://github.com/DaveGamble/cJSON/blob/v1.7.19/cJSON.c#L253-L261 · Note