CVE-2026-54271 json
protobufjs-cli: Code injection in pbjs static output from crafted JSON descriptor names
published 4mo ago modified 17d ago also EUVD-2026-38304 , GHSA-pr59-h9ph-3fr8
- cvss
- 8.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 23%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- npm protobufjs-cli 1.3.2, 2.5.0
- protobufjs_project protobufjs-cli 1.3.2, 2.5.0
Is CVE-2026-54271 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 4mo ago
Exploit prediction
0.30% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.2 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:L |
| GitHub | 3.1 | 8.2 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:L |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | protobufjs-cli | <1.3.2 >=2.0.0, <2.5.0 |
1.3.2 2.5.0 |
Affected products
- protobufjs protobufjs-cli
Classification
- Weakness
-
- CWE-94 Improper Control of Generation of Code
References
-
github.com
/protobufjs/protobuf.js/security/advisories/GHSA-pr59-h9ph-3fr8
web, mitigation, vendor-advisory, advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-54271
advisory
-
github.com
/protobufjs/protobuf.js
package
Sources
- CVE List CVE-2026-54271
- GitHub Advisory GHSA-pr59-h9ph-3fr8
- NVD CVE-2026-54271
- Maintainer advisory GHSA-pr59-h9ph-3fr8
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of protobufjs/protobuf.js published their own advisory on GitHub. Reviewed sources take precedence over it.