{"id":"CVE-2026-54271","aliases":["GHSA-pr59-h9ph-3fr8"],"url":"https://o3.security/vulnerability/CVE-2026-54271","summary":"protobufjs-cli: Code injection in pbjs static output from crafted JSON descriptor names","details":"## Summary\n\nA 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.\n\nThis is a bypass of GHSA-6r35-46g8-jcw9 / CVE-2026-44295.\n\n## Impact\n\nAn 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.\n\nThe injected code may execute if the generated file is later executed or imported and an affected generated API path is invoked.\n\n## Preconditions\n\n* The application or build process must run `pbjs` static code generation on a pre-parsed JSON descriptor influenced by an attacker.\n* The generated JavaScript file must subsequently be executed or imported.\n* An affected generated API path must be invoked.\n\n## Workarounds\n\nDo 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.","published":"2026-06-22T16:16:05.062Z","modified":"2026-08-12T03:51:30.133677701Z","cvss":{"score":8.2,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:L"},"epss":{"score":0.00303,"percentile":0.22447,"asOf":"2026-09-01"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"protobufjs-cli","fixedVersion":"1.3.2"},{"ecosystem":"npm","name":"protobufjs-cli","fixedVersion":"2.5.0"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54271.json"},{"type":"ADVISORY","url":"https://github.com/protobufjs/protobuf.js/security/advisories/GHSA-pr59-h9ph-3fr8"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54271"},{"type":"PACKAGE","url":"https://github.com/protobufjs/protobuf.js"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:30.133677701Z"}}