Description
protobufjs generated JavaScript for toObject conversion could include an unsafe expression derived from a schema-controlled bytes field default value. A crafted descriptor with a non-string default value for a bytes field could cause attacker-controlled code to be emitted into the generated conversion function.
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
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- protobuf.js: Denial of service from crafted field names in generated code - CVE-2026-44294
- protobuf.js: Prototype injection in generated message constructors - CVE-2026-44292
- protobuf.js: Denial of service through unbounded protobuf recursion - CVE-2026-44289
- protobuf.js: Process-wide denial of service through unsafe option paths - CVE-2026-44290


