CVE-2026-67215highCWE-674

CVE-2026-67215: high-severity vulnerability in DaveGamble cJSON

cJSON JSON Patch copy/add Uncontrolled Recursion Stack Exhaustion

Published

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41Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 8.7epss 0.7%
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.
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
Affected products
DaveGamble · cJSON
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