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TI-2026-69599 Aliases CVE-2026-107298GHSA-24ch-f2g6-9hhh

Deeply nested input exhausts the stack in msgpack5 decoder

Priority LOW 30CWE-674Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · Low
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-674.

Summary

msgpack5, a MessagePack v5 implementation for node.js and the browser, has no nesting-depth limit in its array and map decoding paths before 6.1.0. An attacker who can supply MessagePack input can send deeply nested containers that exhaust the JavaScript call stack and interrupt a process, worker, or request handler. The weakness is classified as CWE-674 (Uncontrolled Recursion). CISA's SSVC rates automatable as yes and technical impact as partial, and the CVSS 3.1 base score is 5.3 (MEDIUM).

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00372 31st percentileScored 2026-11-07
Fix Fixed msgpack5 (mcollina): 6.1.0msgpack5 (npm): 6.1.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
mcollinamsgpack5before 6.1.06.1.0Patch availableCNA
—msgpack5 (npm)before 6.1.06.1.0Patch availableGHSA-24ch-f2g6-9hhh
  • msgpack5 Vendormcollina Affected before 6.1.0 Fixed in 6.1.0 Patch available CNA
  • msgpack5 (npm) Vendor— Affected before 6.1.0 Fixed in 6.1.0 Patch available GHSA-24ch-f2g6-9hhh

Remediation

Update msgpack5 to version 6.1.0, the fixed version listed for the npm package.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA msgpack5 (mcollina) Fixed in 6.1.0
  • Fix · GHSA-24ch-f2g6-9hhh msgpack5 (npm) Fixed in 6.1.0 Advisory →

Timeline

  1. 2026-10-08 Threatist record created from CVE-2026-107298
  2. 2026-10-08 Alias added: GHSA-24ch-f2g6-9hhh
  3. 2026-10-09 CISA SSVC decision points changed

References

Other 4

  • TI-2026-76780 Command injection in mcollina mcp-ripgrep Advanced Search Tool CVSS 4.0MEDIUM 4.8
  • TI-2026-69605 Truncated map32 headers throw RangeError in msgpack5 decoder CVSS 3.1HIGH 7.5
  • TI-2026-69603 msgpack5 streaming decoder recursion can exhaust the call stack CVSS 3.1HIGH 7.5
  • TI-2026-69606 Prototype pollution in msgpack5 with partial options CVSS 3.1MEDIUM 6.5
  • TI-2026-69609 Quadratic parsing in msgpack5 streaming decoder blocks the event loop CVSS 3.1MEDIUM 5.9
  • TI-2026-69600 Reserved byte in msgpack5 causes unbounded stream buffering CVSS 3.1MEDIUM 5.9
See all 7 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences