CVE-2026-67215

high

Description

cJSON through 1.7.19 is vulnerable to uncontrolled recursion leading to stack exhaustion when an untrusted RFC 6902 JSON Patch is applied via cJSONUtils_ApplyPatches() or cJSONUtils_ApplyPatchesCaseSensitive(). A patch containing add and copy operations grafts duplicated subtrees to amplify document depth beyond the parser's nesting limit: cJSON_Delete() recurses with no depth bound, and the cJSON_Duplicate() guard CJSON_CIRCULAR_LIMIT is set to 10000, ten times the parser's 1000-level nesting limit and high enough to overflow a default thread stack. An attacker who can supply the patch document can crash the process, resulting in denial of service.

References

https://www.vulncheck.com/advisories/cjson-json-patch-copy-add-uncontrolled-recursion-stack-exhaustion

https://joshua.hu/cjson-json-parser-cve-vulnerabilities

https://github.com/DaveGamble/cJSON/blob/v1.7.19/cJSON_Utils.c#L906-L940

https://github.com/DaveGamble/cJSON/blob/v1.7.19/cJSON.c#L253-L261

Details

Source: Mitre, NVD

Published: 2026-07-29

Updated: 2026-07-30

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

CVSS v4

Base Score: 8.7

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00346