CVE-2026-67216
No fix known EPSS <1%CVSS 5.9
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.
Products: davegamble cjson
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Debian 12 | cjson | no fix |
| Debian 13 | cjson | no fix |
| Debian 14 | cjson | no fix |
| Ubuntu 16.04 LTS | mapcache | no fix |
| Ubuntu 18.04 LTS | mapcache | no fix |
| Ubuntu 20.04 LTS | mapcache | no fix |
| Ubuntu 22.04 LTS | mapcache | no fix |
| Ubuntu 24.04 LTS | mapcache | no fix |
| Ubuntu 26.04 LTS | cjson | no fix |
| Ubuntu 26.04 LTS | iperf3 | no fix |
| Ubuntu 26.04 LTS | mapcache | no fix |
| Ubuntu 26.04 LTS | sail-ocaml | no fix |
| Ubuntu 26.10 | cjson | no fix |
| Ubuntu 26.10 | iperf3 | no fix |
| Ubuntu 26.10 | mapcache | no fix |
| Ubuntu 26.10 | sail-ocaml | no fix |
| Ubuntu Pro 16.04 LTS | iperf3 | no fix |
| Ubuntu Pro 18.04 LTS | iperf3 | no fix |
| Ubuntu Pro 20.04 LTS | cjson | no fix |
| Ubuntu Pro 20.04 LTS | iperf3 | no fix |
| Ubuntu Pro 22.04 LTS | cjson | no fix |
| Ubuntu Pro 22.04 LTS | iperf3 | no fix |
| Ubuntu Pro 24.04 LTS | cjson | no fix |
| Ubuntu Pro 24.04 LTS | iperf3 | no fix |