PatchTheCEVCVE-2026-67216: cJSON through 1.7.19 contains an inefficient algorithmic complexity flaw in cJSON_Compare()
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MEDIUM 5.9REMOTEUPGRADE
CVE-2026-67216 is a medium-severity flaw (CVSS 5.9) affecting cjson. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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 nes
Why this priority
- Public exploit reference
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.9 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | High |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.6% (top 50%) |
| CISA exploited list | No |
| Weakness | CWE-407 |
| Published | 2026-07-29 |
| Last modified | 2026-10-23 |
Publisher (CNA): VulnCheck · Vendor: davegamble
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
davegamble cjson UPGRADE
Affected: <= 1.7.19
Fixed in: newer than 1.7.19
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy cjson || rpm -q cjson || cjson --version
2. UPGRADE to newer than 1.7.19 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade cjson
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade cjson
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Related CVEs
- CVE-2026-67215 HIGH 7.5 UPGRADE cJSON through 1.7.19 is vulnerable to uncontrolled recursion leading to stack exhaustion when an untrusted RFC
- CVE-2026-67217 MEDIUM 5.3 UPGRADE cJSON through 1.7.19 applies RFC 6902 JSON Patch operations non-atomically in apply_patch() in cJSON_Utils.c