CVE-2026-67217: Davegamble Cjson

Medium severity, CVSS 5.3. EPSS: 0.4% chance of exploitation in the next 30 days.

cJSON through 1.7.19 applies RFC 6902 JSON Patch operations non-atomically in apply_patch() in cJSON_Utils.c. For a replace operation that is missing its value member, or a move operation whose destination path cannot be resolved, the existing target member is detached and deleted before the operation is fully validated, so the target document is mutated while cJSONUtils_ApplyPatches() or cJSONUtils_ApplyPatchesCaseSensitive() returns a failure status. An attacker who can supply the patch document can destroy addressable members of the target document even though the API reports that the patch failed, defeating the all-or-nothing behavior callers rely on to reject bad patches.

Affected products

• Davegamble Cjson: up to and including 1.7.19

Published 2026-07-29. Last modified 2026-08-04.