CVE-2026-59876
4.8 · MEDIUMOverview
CVE-2026-59876 is a medium-severity vulnerability affecting protobufjs_project protobufjs. It was published on July 8, 2026 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
protobufjs compiles protobuf definitions into JavaScript (JS) functions. From 8.2.0 until 8.6.5, the protobufjs Text Format extension parsed string-keyed map entries using ordinary property assignment, allowing a map entry with key __proto__ to change the prototype of the returned map object instead of creating an own map entry in protobufjs/ext/textformat. This issue is fixed in version 8.6.5.
Remediation
Check the references section for vendor advisories and patches from protobufjs_project. Update protobufjs to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| protobufjs_project | protobufjs | >= 8.2.0, < 8.6.5 | Affected |
References
Frequently Asked Questions
What is CVE-2026-59876?
CVE-2026-59876 is a medium-severity vulnerability affecting protobufjs_project protobufjs. It was published on July 8, 2026 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
How severe is CVE-2026-59876?
This vulnerability has a CVSS 3.1 base score of 4.8, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-59876?
Check the references section for vendor advisories and patches from protobufjs_project. Update protobufjs to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-59876?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-59876 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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