CVE-2026-42290 — protobufjs-cli
HIGHCVE-2026-42290 is a high-severity (CVSS 7.8) OS Command Injection vulnerability in protobufjs-cli. A fix is available for protobufjs-cli — see the affected versions and patch details below.
protobufjs-cli: OS Command Injection
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-42290.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
protobufjs-clinpmDescription
Summary
pbts invoked JSDoc by building a shell command string from input file paths and executing it through child_process.exec. File paths containing shell metacharacters could therefore be interpreted by the shell instead of being passed to JSDoc as plain arguments.
Impact
An attacker who can control file names or paths passed to pbts may be able to execute arbitrary shell commands with the privileges of the process running pbts.
This affects the protobufjs CLI tooling path. The protobufjs runtime APIs for encoding, decoding, parsing, and loading protobuf messages are not directly affected by this issue.
Preconditions
- The application or user must invoke
pbtson file paths influenced by an attacker. - The attacker must be able to supply or create a path containing shell-significant characters.
- The vulnerable
pbtsversion must execute the generated JSDoc command through a shell.
Workarounds
Do not run affected versions of pbts on attacker-controlled file names or paths. If this cannot be avoided, sanitize or rename input files before invoking pbts, or run the CLI in an isolated environment with minimal privileges.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | protobufjs-cli | all versions | 1.2.1npm install protobufjs-cli@1.2.1 |
| 📦npm | protobufjs-cli | ≥ 2.0.0&&< 2.0.2 | 2.0.2npm install protobufjs-cli@2.0.2 |
Affected Products
protobufjs-cliprotobufjs_projectDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for protobufjs-cli, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update protobufjs-cli to 1.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-42290 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.
Frequently Asked Questions
Is CVE-2026-42290 in your dependencies?
Find it across npm, including transitive dependencies.