CVE-2026-67216 (GCVE-0-2026-67216)

Vulnerability from cvelistv5 – Published: 2026-07-29 13:32 – Updated: 2026-07-30 15:19
VLAI
Title
cJSON cJSON_Compare Exponential Complexity Denial of Service
Summary
cJSON through 1.7.19 contains an inefficient algorithmic complexity flaw in cJSON_Compare(). When comparing objects, the function recurses into each shared subtree twice, once in each direction, with no depth guard, making the running time exponential in nesting depth. A small, deeply nested document of a few hundred bytes (depth around 40) compared for equality consumes hours of CPU, and the cost roughly doubles with each additional level of nesting. An application that calls cJSON_Compare() on attacker-influenced JSON that is structurally equal to a reference document is exposed to a denial-of-service condition.
Severity
8.2 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-30 13:38 UTC
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
Assigner
VulnCheck CNA
References
Impacted products
Vendor Product Version
DaveGamble cJSON Affected: 0 , ≤ 1.7.19 (semver)
    cpe:2.3:a:davegamble:cjson:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-07-25 00:00
Show details on NVD website
To clipboard 

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