CVE-2026-107300
High
Description
msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, the streaming decoder recursively invokes itself for each complete MessagePack value remaining in a chunk. A remote peer can send one chunk containing many small valid values, causing recursion proportional to the value count, exhausting the JavaScript call stack, and interrupting the process or stream. This issue is fixed in version 6.1.0.
SeverityHigh
CVSS7.5
Exploit probability—
ProductMsgpack5
PublishedOct 8, 2026
First seenOct 8, 2026
Weakness typeCWE-674CWE-674
How to fix
Update
- msgpack56.1.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| msgpack5npm | v < 6.1.0 | 6.1.0 |
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