CVE-2026-67216

Publication date 29 July 2026

Last updated 28 August 2026


Ubuntu priority

Cvss 3 Severity Score

5.9 · Medium

Score breakdown

Description

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.

Read the notes from the security team

Status

Package Ubuntu Release Status
cjson 26.04 LTS resolute
Vulnerable, fix deferred
24.04 LTS noble
Vulnerable, fix deferred
22.04 LTS jammy
Vulnerable, fix deferred
20.04 LTS focal
Vulnerable, fix deferred
iperf3 26.04 LTS resolute
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
mapcache 26.04 LTS resolute
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation
sail-ocaml 26.04 LTS resolute
Needs evaluation
24.04 LTS noble Not in release
22.04 LTS jammy Not in release

Notes


mrmajumder

no upstream fix available as of 2026-08-28 for cjson

Severity score breakdown

CVSS version:

Base score 8.2 · High

Vector: 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

Base score 5.9 · Medium

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


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