CVE-2022-39243 is a high-severity (CVSS 8.4) CWE-77 vulnerability in com.zaxxer:nuprocess. 1 public exploit reference exists, so weaponization risk is real. A fix is available for com.zaxxer:nuprocess — see the affected versions and patch details below.
NuProcess vulnerable to command-line injection through insertion of NUL character(s)
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2022-39243.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2022-39243 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
com.zaxxer:nuprocessReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Impact
In all the versions of NuProcess where it forks processes by using the JVM's Java_java_lang_UNIXProcess_forkAndExec method (1.2.0+), attackers can use NUL characters in their strings to perform command line injection. Java's ProcessBuilder isn't vulnerable because of a check in ProcessBuilder.start. NuProcess is missing that check.
This vulnerability can only be exploited to inject command line arguments on Linux.
- On macOS, any argument with a NUL character is truncated at that character. This means the malicious arguments are never seen by the started process.
- On Windows, the entire command line is truncated at the first NUL character. This means the malicious arguments, and any intentional arguments provided after them, are never seen by the started process.
Patches
2.0.5
Workarounds
Users of the library can sanitize command strings to remove NUL characters prior to passing them to NuProcess for execution.
References
None.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | com.zaxxer:nuprocess | ≥ 1.2.0&&< 2.0.5 | 2.0.5com.zaxxer:nuprocess:2.0.5 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for com.zaxxer:nuprocess, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update com.zaxxer:nuprocess to 2.0.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-39243 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2022-39243 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2022-39243. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2022-39243 in your dependencies?
O3 Security finds CVE-2022-39243 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.