CVE-2026-59876

Summary

protobufjs compiles protobuf definitions into JavaScript (JS) functions. From 8.2.0 until 8.6.5, the protobufjs Text Format extension parsed string-keyed map entries using ordinary property assignment, allowing a map entry with key proto to change the prototype of the returned map object instead of creating an own map entry in protobufjs/ext/textformat. This issue is fixed in version 8.6.5.

Affected Software

VendorProductVersion RangeStatus
protobufjsprotobuf.js>= 8.2.0, < 8.6.5affected

Weaknesses

  • CWE-1321: CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

References