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TI-2021-17903 Aliases CVE-2021-41039GHSA-5xp2-36v8-r67m

In versions 1.6 to 2.0.11 of Eclipse Mosquitto, an MQTT v5 client connecting with a large…

Priority LOW 36CWE-1050Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

In versions 1.6 to 2.0.11 of Eclipse Mosquitto, an MQTT v5 client connecting with a large number of user-property properties could cause excessive CPU usage, leading to a loss of performance and possible denial of service.

Why it matters now

EPSS 0.01355 71st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
Eclipse FoundationEclipse Mosquitto1.6 and later; up to 2.0.11—No fix listedCNA
  • Eclipse Mosquitto VendorEclipse Foundation Affected 1.6 and later; up to 2.0.11 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:eclipse:mosquitto:*:*:*:*:*:*:*:*1.6 – 2.0.11VulnerableEclipse Foundation
  • cpe:2.3:a:eclipse:mosquitto:*:*:*:*:*:*:*:* Versions 1.6 – 2.0.11 Vulnerable ·Eclipse Foundation

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-41039
  2. 2026-10-03 Alias added: GHSA-5xp2-36v8-r67m

References

  • TI-2024-09749 Eclipse Mosquito: Heap Buffer Overflow in my_subscribe_callback CVSS 4.0HIGH 7.2
  • TI-2018-09002 Reachable assertion in Eclipse Mosquitto CVSS 3.0HIGH 7.5
  • TI-2023-12912 The broker in Eclipse Mosquitto 1.3.2 through 2.x before 2.0.16 has a memory leak that… CVSS 3.1HIGH 7.5
  • TI-2017-05287 Uncontrolled resource consumption in Eclipse Mosquitto CVSS 3.0HIGH 7.5
  • TI-2023-05183 Unconditionally adding an event to the epoll causes excessive CPU consumption CVSS 3.1HIGH 7.5
  • TI-2018-09010 Improper authentication in Eclipse Mosquitto CVSS 3.0HIGH 8.1
See all 25 →

Sources