Review reviewHigh

CVE-2026-54271

protobufjs protobufjs-cli

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...

CVSS: 8.2
EPSS: 0.30%
CISA KEV: Not listed
Published: 2026.06.23

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.30%

Technical severityCVSS 8.2

Vulnerability overview

Affected product and versions

Product: protobufjs protobufjs-cli
Affected versions: < 1.3.2, >= 2.0.0, < 2.4.2, >= 2.0.0 < 2.5.0
Fixed versions: 1.3.2, 2.5.0

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that protobufjs protobufjs-cli and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:L
CWE: CWE-94