CVE-2026-44295: protobufjs-cli code injection in pbjs static code generation

CVE-2026-44295 · Severity: high · CVSS 8.7 · Published 2026-05-13

protobufjs-cli is a command-line tool used to generate JavaScript code from Protocol Buffer schemas. A vulnerability in the code generation process allows an attacker to provide a specially crafted schema that injects malicious code into the resulting JavaScript files. If a developer or automated build system processes an untrusted schema and then executes the generated code, it could lead to a full system compromise or data theft.

Technologies: protobufjs-cli (npm). Vendors: npm.

Quick answers

Is CVE-2026-44295 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-44295 being exploited in the wild.
How severe is CVE-2026-44295?
High severity, with a CVSS score of 8.7, published 13 May 2026.
Which products and versions are affected?
protobufjs-cli (npm) SEMVER:introduced=0,fixed=1.2.1.
Is there a fix for CVE-2026-44295?
Yes. protobufjs-cli (npm): upgrade to 1.2.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-44295 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-44295?
Check whether you run protobufjs-cli (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • protobufjs-cli (npm): upgrade to 1.2.1 or later
    npm install protobufjs-cli@1.2.1

Technical details

A code injection vulnerability (CWE-94) exists in the pbjs static code generation component of protobufjs-cli. The root cause is insufficient sanitization of identifiers derived from schema-controlled names, such as namespaces, enums, and service names. An attacker can craft a malicious .proto schema or JSON descriptor that, when processed by pbjs, embeds arbitrary JavaScript into the output file. Exploitation requires the attacker to influence the schema used during the build process and for the victim to subsequently execute or import the generated JavaScript. This vulnerability is fixed in versions 1.2.1 and 2.0.2.

Affected products

  • protobufjs protobufjs-cli < 1.2.1, >= 2.0.0 < 2.0.2

Identifiers

  • CVE-2026-44295
  • GHSA-6r35-46g8-jcw9

Timeline

  • 2026-05-12: advisory: GitHub Security Advisory GHSA-6r35-46g8-jcw9 published
  • 2026-05-13: disclosed: CVE-2026-44295 published to NVD

References

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