RCE in Protobufjs Protobuf.js

CVE-2026-44295

protobufjs-cli is the command line add-on for protobuf.js. Prior to 1.2.1 and 2.0.2, pbjs static code generation could emit unsafe JavaScript identifiers derived from schema-controlled names. When generating static JavaScript from a crafted schema or JSON descriptor, certain namespace, enum, service, or derived full names could be written into the generated output without sufficient sanitization. This vulnerability is fixed in 1.2.1 and 2.0.2.

Vulnerability class: RCE (Remote Code Execution)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.004 (27.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 27.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-44295: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: -0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-44295?
CVE-2026-44295 is a high-severity vulnerability in Protobufjs Protobuf.js, classified under Code Injection. CVSS score: 8.7/10. Published 2026-05-13.
How severe is CVE-2026-44295?
High severity. CVSS v3 base score is 8.7 out of 10.