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.
cJSON JSON Patch copy/add Uncontrolled Recursion Stack Exhaustion
cJSON cJSONCompare Exponential Complexity Denial of Service
cJSON 1.7.15 might allow a denial of service via a crafted JSON document such as {"a": true, "b": [ null,9999999999999999999999999999999999999999999999912345678901234567]}.
cJSON versions 1.5.0 through 1.7.19 contain an incorrectly-resolved name or reference vulnerability in the decodepointerinplace() function within cJSONUtils.c that allows unauthenticated attackers to cause JSON Patch operations to target wrong object keys by supplying crafted JSON Pointer escape sequences (~0 or ~1) in patch paths. Attackers can submit malicious RFC 6902 JSON Patch input to applications using cJSONUtilsApplyPatches() or cJSONUtilsApplyPatchesCaseSensitive() to silently corrupt data or delete unintended keys, potentially bypassing authorization controls in applications that rely on JSON Patch for access-controlled data modification.
parsestring in cJSON before 1.7.18 has a heap-based buffer over-read via {"1":1, with no trailing newline if cJSONParseWithLength is called.
cJSON 1.5.0 through 1.7.18 allows out-of-bounds access via the decodearrayindexfrompointer function in cJSONUtils.c, allowing remote attackers to bypass array bounds checking and access restricted data via malformed JSON pointer strings containing alphanumeric characters.
cJSON 1.5.0 through 1.7.18 allows out-of-bounds access via the decodearrayindexfrompointer function in cJSONUtils.c, allowing remote attackers to bypass array bounds checking and access restricted data via malformed JSON pointer strings containing alphanumeric characters.
cJSON v1.7.16 was discovered to contain a segmentation violation via the function cJSONSetValuestring at cJSON.c.
https://github.com/DaveGamble/cJSON/issues/803