Medium severity · published Oct 8, 2026
CVE-2026-107298
msgpack5: Deeply nested input can exhaust the decoder stack
5.3
CVSS
0.4%
EPSS
No
On KEV
Description
msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, the array and map decoding paths have no nesting-depth limit, allowing an attacker who can provide MessagePack input to submit deeply nested containers that exhaust the JavaScript call stack and interrupt a process, worker, or request handler. This issue is fixed in version 6.1.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 31% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MS
msgpack5 · mcollina
< 6.1.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-107298
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-107298
x_refsource_CONFIRM
https://github.com/mcollina/msgpack5/security/advisories/GHSA-24ch-f2g6-9hhh
x_refsource_MISC
https://github.com/mcollina/msgpack5/commit/1e2b5874e555dd7c99417f64788a03b0590bb102
x_refsource_MISC
https://github.com/mcollina/msgpack5/releases/tag/v6.1.0
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