CVE-2026-44292
protobufjs: Prototype injection in generated message constructors
CVSS Score
5.3
EPSS Score
0.0%
EPSS Percentile
0th
protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.5.6 and 8.0.2, 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. This vulnerability is fixed in 7.5.6 and 8.0.2.
| CWE | CWE-1321 |
| Vendor | protobufjs |
| Product | protobuf.js |
| Published | May 13, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Affected Versions
protobufjs / protobuf.js
< 7.5.6 >= 8.0.0, < 8.0.2