CVE-2026-107300

Status: DeferredHigh (7.5)—

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.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base score: 7.5

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.43%
Percentile among all scored CVEs: 35
Score date: 10/13/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access95 %
Primary impactT1499.004 Application or System Exploitationimpact90 %

Vector CVSS de red sin autenticación (AV:N/PR:N/UI:N) + CWE-674 (stack exhaustion) y descripción que un atacante remoto causa recursión excesiva causando negación de servicio al agotar el call stack.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Filter Network Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Application Isolation and Sandboxing

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Msgpack5 — Msgpack5^AI

CWEs

CWE-674

References

Raw JSON (NVD)

Show

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          "options": [
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          "version": "2.0.3",
          "timestamp": "2026-10-08T17:52:32.790652Z"
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          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
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          "attackComplexity": "LOW",
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  "published": "2026-10-08T17:17:16.000",
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  "lastModified": "2026-10-08T20:48:36.970",
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