CVE-2026-67216
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Summary
cJSON through 1.7.19 contains an inefficient algorithmic complexity flaw in cJSON_Compare(). When comparing objects, the function recurses into each shared subtree twice, once in each direction, with no depth guard, making the running time exponential in nesting depth. A small, deeply nested document of a few hundred bytes (depth around 40) compared for equality consumes hours of CPU, and the cost roughly doubles with each additional level of nesting. An application that calls cJSON_Compare() on attacker-influenced JSON that is structurally equal to a reference document is exposed to a denial-of-service condition.
Affected Software
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| DaveGamble | cJSON | 0 <= 1.7.19 | affected |
Weaknesses
- CWE-407: Inefficient Algorithmic Complexity
References
- https://joshua.hu/cjson-json-parser-cve-vulnerabilities
- https://github.com/DaveGamble/cJSON/blob/v1.7.19/cJSON.c#L3057-L3180
- https://www.vulncheck.com/advisories/cjson-cjson-compare-exponential-complexity-denial-of-service
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