protobufjs: Code generation gadget after prototype pollution
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.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-44291
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 6 Nov 2026, 19:06 UTC · Revision 1
Source evidence
protobufjs: Code generation gadget after prototype pollution
core-osv · Original sourcePublished 13 May 2026, 14:42 UTC
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.
osv:CVE-2026-44291
Complete source record
{
"id": "35684020077374efaff0e7e584d4a3af17caacbdb72772cda6983265445ccd48",
"url": "https://osv.dev/vulnerability/CVE-2026-44291",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "protobufjs: Code generation gadget after prototype pollution",
"summary": "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.",
"evidence": "osv:CVE-2026-44291",
"products": [],
"severity": "high",
"structured": {
"id": "CVE-2026-44291",
"aliases": [
"CVE-2026-44291",
"GHSA-75px-5xx7-5xc7"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/protobufjs/protobuf.js",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "2189e5beeca6a70e4c104dfdb9fb8200bc5f81fe"
},
{
"introduced": "933e8750dcd000c16a621a7344a4beaa034c4019"
},
{
"fixed": "658b93e163d9aff8c31236c168657bab5e2d9bbc"
}
],
"database_specific": {
"extracted_events": [
{
"cpe": "cpe:2.3:a:protobufjs_project:protobufjs:*:*:*:*:*:node.js:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "7.5.6"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:protobufjs_project:protobufjs:*:*:*:*:*:node.js:*:*",
"range": [
{
"introduced": "8.0.0"
},
{
"fixed": "8.0.2"
}
],
"source": "CPE_RANGE"
}
]
}
}
],
"versions": [
"protobufjs-v7.5.5",
"protobufjs-v8.0.1",
"protobufjs-cli-v2.0.1",
"protobufjs-v7.5.4",
"protobufjs-v8.0.0",
"protobufjs-cli-v2.0.0",
"protobufjs-v7.5.3",
"protobufjs-v7.5.2",
"protobufjs-v7.5.1",
"protobufjs-v7.5.0",
"protobufjs-cli-v1.2.0",
"protobufjs-v7.4.0",
"protobufjs-cli-v1.1.4",
"protobufjs-v7.3.3",
"protobufjs-cli-v1.1.3",
"protobufjs-v7.3.2",
"protobufjs-v7.3.1",
"protobufjs-v7.3.0",
"protobufjs-v7.2.6",
"protobufjs-v7.2.5",
"protobufjs-cli-v1.1.2",
"protobufjs-v7.2.4",
"protobufjs-v7.2.3",
"protobufjs-v7.2.2",
"protobufjs-v7.2.1",
"protobufjs-cli-v1.1.1",
"protobufjs-v7.2.0",
"protobufjs-cli-v1.1.0",
"protobufjs-v7.1.2",
"protobufjs-v7.1.1",
"protobufjs-cli-v1.0.2",
"protobufjs-v7.1.0",
"protobufjs-cli-v1.0.1",
"protobufjs-v7.0.0",
"protobufjs-cli-v1.0.0",
"v6.10.2",
"v6.10.1",
"v6.10.1-beta.0",
"v6.10.0",
"v6.10.0-beta.2",
"v6.10.0-beta.1",
"v6.10.0-beta.0",
"v6.9.0",
"v6.9.0-beta.0",
"6.8.8",
"6.8.7",
"6.8.6",
"6.8.5",
"6.8.4",
"6.8.3",
"6.8.2",
"6.8.1",
"6.8.0",
"6.7.3",
"6.7.2",
"6.7.1",
"6.7.0",
"6.6.5",
"6.6.4",
"6.6.3",
"6.6.2",
"6.6.1",
"6.6.0",
"6.5.3",
"6.5.2",
"6.5.1",
"6.5.0",
"6.4.6",
"6.4.5",
"6.4.4",
"6.4.3",
"6.4.2",
"6.4.1",
"6.4.0",
"6.3.1",
"6.3.0",
"6.2.1",
"6.2.0",
"6.1.1",
"6.1.0",
"6.0.2",
"6.0.1",
"6.0.0"
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-44291.json"
}
}
],
"modified": "2026-10-28T02:30:47.825737703Z",
"provider": "osv",
"references": [
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44291.json",
"https://github.com/protobufjs/protobuf.js/security/advisories/GHSA-75px-5xx7-5xc7",
"https://nvd.nist.gov/vuln/detail/CVE-2026-44291"
],
"provider_metadata": {
"cwe_ids": [
"CWE-94"
],
"cna_assigner": "GitHub_M",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44291.json"
}
},
"related_cves": [
{
"value": "CVE-2026-44291",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 515941,
"published_at": "2026-05-13T14:42:13.984+00:00"
}