CVE-2026-29036

cJSON versions 1.5.0 through 1.7.19 contain an incorrectly-resolved name or reference vulnerability in the decode_pointer_inplace() function within cJSON_Utils.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 cJSONUtils_ApplyPatches() or cJSONUtils_ApplyPatchesCaseSensitive() to silently corrupt data or delete unintended keys, potentially bypassing authorization controls in applications that rely on JSON Patch for access-controlled data modification.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/DaveGamble/cJSON
https://www.vulncheck.com/advisories/cjson-wrong-key-modification-via-json-pointer-escape-decoding

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-11 22:17

Updated : 2026-08-13 16:18

NVD link : CVE-2026-29036

Mitre link : CVE-2026-29036

CVE.ORG link : CVE-2026-29036

JSON object : View

Products Affected

No product.

CWE

CWE-706

Use of Incorrectly-Resolved Name or Reference

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