CVE-2026-67217

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/DaveGamble/cJSON/blob/v1.7.19/cJSON_Utils.c#L887-L948	Patch
https://joshua.hu/cjson-json-parser-cve-vulnerabilities	Exploit Press/Media Coverage Third Party Advisory
https://www.vulncheck.com/advisories/cjson-json-patch-non-atomic-application-destroys-data-before-validation	Third Party Advisory
https://joshua.hu/cjson-json-parser-cve-vulnerabilities	Exploit Press/Media Coverage Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:davegamble:cjson:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-29 14:16

Updated : 2026-08-04 15:03

NVD link : CVE-2026-67217

Mitre link : CVE-2026-67217

CVE.ORG link : CVE-2026-67217

JSON object : View

Products Affected

davegamble

cjson

CWE

CWE-696

Incorrect Behavior Order

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