CVE-2026-54271
Published: 22 June 2026
Summary
CVE-2026-54271 is a high-severity Code Injection (CWE-94) vulnerability in Protobufjs Project Protobufjs-Cli. Its CVSS base score is 8.2 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique JavaScript (T1059.007); ranked at the 13.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-38304
Vulnerability details
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…
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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.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Direct code injection into generated JavaScript (CWE-94) enables attacker-controlled code execution via JS interpreter when output is imported/executed.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Makes persistent code injection into loaded programs impossible when the executable image itself resides on hardware-protected read-only media.
Dynamically generated code can be produced and executed inside the isolated chamber, preventing host compromise from code-injection payloads.
Validates inputs used in dynamic code generation to block injected directives.
Directly prevents execution of attacker-supplied code written into data memory regions.