CVE-2026-59877
Last modified
CVE-2026-59877 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.6.5 and 8.6.6, protobufjs parsed option names by advancing through schema tokens until reaching an = token without checking for end of input, so a crafted .proto schema that opens an option declaration and ends prematurely can cause parse, Root.load, or Root.loadSync to loop indefinitely. EPSS estimates a 0.33% chance of exploitation in the next 30 days.
Description
protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.6.5 and 8.6.6, protobufjs parsed option names by advancing through schema tokens until reaching an = token without checking for end of input, so a crafted .proto schema that opens an option declaration and ends prematurely can cause parse, Root.load, or Root.loadSync to loop indefinitely. This issue is fixed in versions 7.6.5 and 8.6.6.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Protobufjs Project | Protobufjs | < 7.6.5 |
| Protobufjs Project | Protobufjs | >= 8.0.0, < 8.6.6 |
References
- https://github.com/protobufjs/protobuf.js/pull/2352Issue Tracking, Patch
- https://github.com/protobufjs/protobuf.js/releases/tag/protobufjs-v7.6.5Product, Release Notes
- https://github.com/protobufjs/protobuf.js/releases/tag/protobufjs-v8.6.6Product, Release Notes
- https://github.com/protobufjs/protobuf.js/security/advisories/GHSA-j3f2-48v5-ccwwMitigation, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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