Description
The streaming decoder recursively invokes itself for every complete value remaining in a chunk. A single chunk containing many small valid MessagePack values can exhaust the JavaScript call stack and interrupt the process or stream.
Recommendation
Update the msgpack5 package to the latest compatible version. Followings are version details:
- Affected version(s): < 6.1.0
- Patched version(s): 6.1.0
References
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Start a free scanRelated Issues
- msgpack5: Deeply nested input can exhaust the decoder stack - CVE-2026-107298
- msgpack5: Quadratic parsing in the streaming decoder - CVE-2026-107297
- Axios: Nested axios option objects can consume polluted prototype values - CVE-2026-67319
- msgpack5: Reserved byte can cause unbounded stream buffering - CVE-2026-107299
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See something that needs correcting? Let us knowUpdated October 08, 2026