{"id":"CVE-2026-67216","summary":"cJSON cJSON_Compare Exponential Complexity Denial of Service","details":"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.","modified":"2026-08-01T08:06:15.443139Z","published":"2026-07-29T13:32:03.696Z","database_specific":{"cna_assigner":"VulnCheck","cwe_ids":["CWE-407"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67216.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67216.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-67216"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/cjson-cjson-compare-exponential-complexity-denial-of-service"},{"type":"ARTICLE","url":"https://github.com/DaveGamble/cJSON/blob/v1.7.19/cJSON.c#L3057-L3180"},{"type":"EVIDENCE","url":"https://joshua.hu/cjson-json-parser-cve-vulnerabilities"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/davegamble/cjson","events":[{"introduced":"0"},{"fixed":"c859b25da02955fef659d658b8f324b5cde87be3"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"last_affected":"1.7.19"},{"fixed":"1.7.19"}],"source":["AFFECTED_FIELD","DESCRIPTION"]}}],"versions":["v1.7.18","v1.7.17","v1.7.16","v1.7.15","v1.7.14","v1.7.13","v1.7.12","v1.7.11","v1.7.10","v1.7.9","v1.7.8","v1.7.7","v1.7.6","v1.7.5","v1.7.4","v1.7.3","v1.7.2","v1.7.1","v1.7.0","v1.6.0","v1.5.9","v1.5.8","v1.5.7","v1.5.6","v1.5.5","v1.5.4","v1.5.3","v1.5.2","v1.5.1","v1.5.0","v1.4.7","v1.4.6","v1.4.5","v1.4.4","v1.4.3","v1.4.2","v1.4.1","v1.4.0","v1.3.2","v1.3.1","v1.3.0","v1.2.1","v1.2.0","v1.1.0","v1.0.2","v1.0.1","v1.0.0","v0.0.0"],"database_specific":{"vanir_signatures_modified":"2026-08-01T08:06:15Z","vanir_signatures":[{"source":"https://github.com/davegamble/cjson/commit/c859b25da02955fef659d658b8f324b5cde87be3","target":{"file":"cJSON.c"},"deprecated":false,"digest":{"line_hashes":["324212209976151655889958665598298635544","57000550816535391230572611048963131217","217784711622956909858859487036437801772","143000211397577675930366937432594758406"],"threshold":0.9},"id":"CVE-2026-67216-83e2c045","signature_type":"Line","signature_version":"v1"}],"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-67216.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"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"}]}