protobuf.js: Prototype injection in generated message constructors

Description

protobufjs generated message constructors copied enumerable properties from a provided properties object without filtering the __proto__ key. If an application constructed a message from an attacker-controlled plain object, an own enumerable __proto__ property could alter the prototype of that individual message instance.

Recommendation

Update the protobufjs package to the latest compatible version. Followings are version details:

• Affected version(s): **>= 8.0.0, <= 8.0.1

  <= 7.5.5**

• Patched version(s): **8.0.2

  7.5.6**

References

• GHSA-fx83-v9x8-x52w
• CVE-2026-44292
• CWE-1321
• CAPEC-310
• OWASP 2021-A6

Related Issues

• protobuf.js: Code injection through bytes field defaults in generated toObject code - CVE-2026-44293
• protobuf.js: Denial of service from crafted field names in generated code - CVE-2026-44294
• protobuf.js: Code generation gadget after prototype pollution - CVE-2026-44291
• Axios has prototype pollution read-side gadgets in HTTP adapter that allow credential injection and request hijacking - CVE-2026-42264

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Tags:

npm

protobufjs