CVE-2026-41242: protobufjs · Arbitrary Code Execution
Affects protobufjsSource GCVE Database
Not known to be exploited · CVSS 9.4 Critical : upgrade to 8.0.1 as a priority.
Data as of 27 Oct 2026, 00:07 UTC
- Patch
- Available – fixed in 8.0.1, 7.5.5
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:HExploitation evidence
Disclosed: evidence found.
CVE published 18 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade protobufjs to 8.0.1; protobufjs to 7.5.5.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| npmprotobufjs | Affected
| Fixed in
|
| npmprotobufjs | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
## Summary protobufjs could execute generated JavaScript code derived from protobuf schema metadata. When loading a crafted JSON descriptor, schema-controlled type names and type references could reach runtime code generation without sufficient validation. ## Impact An attacker who can provide a malicious protobuf definition or JSON descriptor to an application may be able to execute arbitrary JavaScript in the context of the process using protobufjs. This requires control over the protobuf schema or descriptor being loaded. Applications that only decode messages using trusted, application-defined schemas are not directly affected by this issue. ## Preconditions - The application must allow an attacker to control or influence a protobuf definition or JSON descriptor. - The application must load that definition through protobufjs reflection APIs such as descriptor loading. - The affected generated-code path must be reached, for example by performing an operation on the loaded type. ## Workarounds Do not load protobuf definitions or JSON descriptors from untrusted sources with affected versions. If untrusted schemas must be accepted, validate or restrict them before loading and run schema processing in an isolated environment.
References
- github.com/protobufjs/protobuf.js/security/advisories/GHSA-xq3m-2v4x-88gg (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-41242 (opens in a new tab)
- github.com/protobufjs/protobuf.js/commit/535df444ac060243722ac5d672db205e5c531d75 (opens in a new tab)
- github.com/protobufjs/protobuf.js/commit/ff7b2afef8754837cc6dc64c864cd111ab477956 (opens in a new tab)
- github.com/protobufjs/protobuf.js (opens in a new tab)
- github.com/protobufjs/protobuf.js/releases/tag/protobufjs-v7.5.5 (opens in a new tab)
- github.com/protobufjs/protobuf.js/releases/tag/protobufjs-v8.0.1 (opens in a new tab)