RCE in Protobufjs Protobufjs-Cli
CVE-2026-54271
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.
Vulnerability class: RCE (Remote Code Execution)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:L.
EPSS exploit prediction
EPSS: 0.003 (20.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 20.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Protobufjs Protobufjs-Cli — versions < 1.3.2, >= 2.0.0, < 2.4.2
- Protobufjs Project Protobufjs-Cli
Weakness classification (CWE)
References
- github.com/protobufjs/protobuf.js/security/advisories/GHSA-pr59-h9ph-3fr8 (Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-54271?
- CVE-2026-54271 is a high-severity vulnerability in Protobufjs Protobufjs-Cli, classified under Code Injection. CVSS score: 8.2/10. Published 2026-06-22.
- How severe is CVE-2026-54271?
- High severity. CVSS v3 base score is 8.2 out of 10.