# CVE-2026-44295: protobufjs-cli — Fixed in 1.2.1

📦

📦 npm

Not in CISA KEV

HIGH severity

# CVE-2026-44295 — protobufjs-cli

HIGH 

CVE-2026-44295 is a high-severity (CVSS 8.7) Code Injection vulnerability in protobufjs-cli. A fix is available for protobufjs-cli — see the affected versions and patch details below.

protobufjs-cli: Code injection in pbjs static output from crafted schema names

Also known as[GHSA-6r35-46g8-jcw9](/vulnerability/GHSA-6r35-46g8-jcw9)

Published

May 13, 2026

Updated

Oct 28, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Nov 8, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

## 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-2026-44295.

## EPSS Exploitation Probability

[via FIRST.org ↗](https://www.first.org/epss/)

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs34th percentile — riskier than 34% of all scored CVEsHighest risk

0.00%0.30%0.60%0.90%0.0%0.4%Jun 26Sep 26Nov 26

Probability of exploitation in the next 30 days, from [FIRST.org EPSS](https://www.first.org/epss/).

## How urgent is this, really

## Where this sits among everything scored

## Real-World Exposure

2 pkgs affected

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.

82other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

`protobufjs-cli`npm

2.2Mdownloads / week

## Description

### Summary

`pbjs` static code generation could emit unsafe JavaScript identifiers derived from schema-controlled names. When generating static JavaScript from a crafted schema or JSON descriptor, certain namespace, enum, service, or derived full names could be written into the generated output without sufficient sanitization.

### Impact

An attacker who can provide or influence schemas passed to `pbjs` may be able to cause generated JavaScript output to contain attacker-controlled code. The injected code would run if the generated file is later executed or imported by the application or build process.

This affects the protobufjs CLI static code generation path. Applications that only use trusted schemas, or that do not execute generated output from untrusted schemas, are not directly affected.

### Preconditions

-   The application or build process must run `pbjs` static code generation on a schema or JSON descriptor influenced by an attacker.
-   The attacker-controlled input must contain crafted schema names that reach generated JavaScript output.
-   The generated JavaScript file must subsequently be executed, imported, or otherwise evaluated.

### Workarounds

Do not run affected versions of `pbjs` static code generation on untrusted schemas or descriptors. If untrusted schemas must be accepted, validate schema names before code generation and run generation in an isolated environment.

## Affected Packages

2 total 2 fixed

Ecosystem

Package

Vulnerable range

Fix

📦npm

`protobufjs-cli` 

all versions

1.2.1`npm install protobufjs-cli@1.2.1`

📦npm

`protobufjs-cli` 

≥ 2.0.0&&< 2.0.2

2.0.2`npm install protobufjs-cli@2.0.2`

## Affected Products

1 product · 2 configurations

Application

`protobufjs-cli`protobufjs\_project

≥ 2.0.0 && < 2.0.2

range

## Detection & mitigation playbook

Open-source dependency

1.  ### Detect
    
    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.
    
2.  ### 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-2026-44295 is resolved across your whole dependency graph.
    
3.  ### 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

\## Summary \`pbjs\` static code generation could emit unsafe JavaScript identifiers derived from schema-controlled names. When generating static JavaScript from a crafted schema or JSON descriptor, certain namespace, enum, service, or derived full names could be written into the generated output without sufficient sanitization. ## Impact An attacker who can provide or influence schemas passed to \`pbjs\` may be able to cause generated JavaScript output to contain attacker-controlled code. The injected code would run if the generated file is later executed or imported by the application or build

O3 Security · Impact-Aware SCA

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