CVE-2026-44291: high-severity vulnerability in protobufjs protobuf.js
protobufjs: Code generation gadget after prototype pollution
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.1epss 0.5%
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.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
protobufjs · protobuf.jsRelated CVEs — protobufjs protobuf.js
In the same product, most dangerous first.
CVE-2026-41242CRITICALprotobufjs has an arbitrary code execution issueEPSS 0.8%CVE-2026-44289HIGHprotobufjs: Denial of service through unbounded protobuf recursionEPSS 0.6%CVE-2026-48712HIGHprotobufjs: Denial of service through unbounded Any expansion during JSON conversionEPSS 0.5%CVE-2026-44294MEDIUMprotobufjs: Denial of service from crafted field names in generated codeEPSS 0.4%CVE-2026-44293HIGHprotobufjs: Code injection through bytes field defaults in generated toObject codeEPSS 0.4%CVE-2026-54269MEDIUMprotobufjs: Schema-derived names can shadow runtime-significant propertiesEPSS 0.4%