Description
protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.5.6 and 8.0.2, protobufjs used plain objects with inherited prototypes for internal type lookup tables used by generated encode and decode functions. If Object.prototype had already been polluted, those lookup tables could resolve attacker-controlled inherited properties as valid protobuf type information. This could cause attacker-controlled strings to be emitted into generated JavaScript code. This vulnerability is fixed in 7.5.6 and 8.0.2.
Affected products
protobufjs_project: protobufjs
References1
- github.com/protobufjs/protobuf.js/security/advisories/GHSA-75px… MitigationVendor Advisory
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 43 · as of 14 November 2026
- CWE
- CWE-94
Could this be exploited in your environment?
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