cJSON JSON Patch copy/add Uncontrolled Recursion Stack Exhaustion

cJSON cJSONCompare Exponential Complexity Denial of Service

cJSON through 1.7.19 applies RFC 6902 JSON Patch operations non-atomically in applypatch() in cJSONUtils.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 cJSONUtilsApplyPatches() or cJSONUtilsApplyPatchesCaseSensitive() 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.

cJSON library is vulnerable to an integer overflow in the printstringptr() function in cJSON.c on 32-bit platforms. The escapecharacters counter, a 32-bit sizet, can wrap around when processing strings containing approximately 858,993,460 or more control characters, causing the output buffer to be allocated based on an underestimated length. When cJSONPrintBuffered() is used with a pre-allocated buffer, the subsequent write loop overflows the heap allocation. An attacker supplying a crafted JSON string to an application using cJSON on a 32-bit platform can cause a heap buffer overflow, potentially leading to remote code execution, information disclosure, or denial of service.

Because project creator contact attempts were unsuccessful, the vulnerability has only been confirmed in version 1.7.19 but may also affect other versions.