protobufjs-cli is the command line add-on for protobuf.js. Prior to 1.3.2 and 2.5.0, a previous fix for unsafe name handling in pbjs static / static-module code generation was incomplete. Affected versions of protobufjs-cli could still emit unsafe JavaScript references when generating static output from crafted JSON descriptor input. The common case of parsing schemas from .proto files is not affected. This is a bypass of CVE-2026-44295. An attacker who can provide or influence pre-parsed JSON descriptors passed to pbjs static code generation may be able to cause generated JavaScript output to contain attacker-controlled code. The injected code may execute if the generated file is later executed or imported and an affected generated API path is invoked. This vulnerability is fixed in 1.3.2 and 2.5.0.
protobufjs-cli: Code injection in pbjs static output from crafted JSON descriptor names
Problem type
Affected products
protobufjs
< 1.3.2 - AFFECTED
>= 2.0.0, < 2.4.2 - AFFECTED
References
GitHub Security Advisories
GHSA-pr59-h9ph-3fr8
protobufjs-cli: Code injection in pbjs static output from crafted JSON descriptor names
https://github.com/advisories/GHSA-pr59-h9ph-3fr8Summary
A previous fix for unsafe name handling in pbjs static / static-module code generation was incomplete. Affected versions of protobufjs-cli could still emit unsafe JavaScript references when generating static output from crafted JSON descriptor input. The common case of parsing schemas from .proto files is not affected.
This is a bypass of GHSA-6r35-46g8-jcw9 / CVE-2026-44295.
Impact
An attacker who can provide or influence pre-parsed JSON descriptors passed to pbjs static code generation may be able to cause generated JavaScript output to contain attacker-controlled code.
The injected code may execute if the generated file is later executed or imported and an affected generated API path is invoked.
Preconditions
- The application or build process must run
pbjsstatic code generation on a pre-parsed JSON descriptor influenced by an attacker. - The generated JavaScript file must subsequently be executed or imported.
- An affected generated API path must be invoked.
Workarounds
Do not run affected versions of pbjs static or static-module generation on untrusted JSON descriptors. If untrusted JSON descriptors must be accepted, validate descriptor-derived names before code generation and reject names that could not have been produced by parsing a valid .proto file. Running code generation in an isolated environment can reduce impact.
JSON source
https://cveawg.mitre.org/api/cve/CVE-2026-54271Click to expand
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"cveMetadata": {
"cveId": "CVE-2026-54271",
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"dateUpdated": "2026-06-22T16:16:05.062Z",
"dateReserved": "2026-06-12T17:13:32.280Z",
"datePublished": "2026-06-22T16:16:05.062Z",
"state": "PUBLISHED"
},
"containers": {
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"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M",
"dateUpdated": "2026-06-22T16:16:05.062Z"
},
"title": "protobufjs-cli: Code injection in pbjs static output from crafted JSON descriptor names",
"descriptions": [
{
"lang": "en",
"value": "protobufjs-cli is the command line add-on for protobuf.js. Prior to 1.3.2 and 2.5.0, a previous fix for unsafe name handling in pbjs static / static-module code generation was incomplete. Affected versions of protobufjs-cli could still emit unsafe JavaScript references when generating static output from crafted JSON descriptor input. The common case of parsing schemas from .proto files is not affected. This is a bypass of CVE-2026-44295. An attacker who can provide or influence pre-parsed JSON descriptors passed to pbjs static code generation may be able to cause generated JavaScript output to contain attacker-controlled code. The injected code may execute if the generated file is later executed or imported and an affected generated API path is invoked. This vulnerability is fixed in 1.3.2 and 2.5.0."
}
],
"affected": [
{
"vendor": "protobufjs",
"product": "protobufjs-cli",
"versions": [
{
"version": "< 1.3.2",
"status": "affected"
},
{
"version": ">= 2.0.0, < 2.4.2",
"status": "affected"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"lang": "en",
"description": "CWE-94: Improper Control of Generation of Code ('Code Injection')",
"cweId": "CWE-94",
"type": "CWE"
}
]
}
],
"references": [
{
"url": "https://github.com/protobufjs/protobuf.js/security/advisories/GHSA-pr59-h9ph-3fr8",
"name": "https://github.com/protobufjs/protobuf.js/security/advisories/GHSA-pr59-h9ph-3fr8",
"tags": [
"x_refsource_CONFIRM"
]
}
],
"metrics": [
{
"cvssV3_1": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:L",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "CHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "LOW",
"baseScore": 8.2,
"baseSeverity": "HIGH"
}
}
]
}
}
}