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TI-2021-17309 Aliases CVE-2021-40114GHSA-5v43-2p8q-45m6

Multiple Cisco Products Snort Memory Leak Denial of Service Vulnerability

Priority LOW 38CWE-770Published · 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 · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-770.

Summary

Multiple Cisco products are affected by a vulnerability in the way the Snort detection engine processes ICMP traffic that could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to improper memory resource management while the Snort detection engine is processing ICMP packets. An attacker could exploit this vulnerability by sending a series of ICMP packets through an affected device. A successful exploit could allow the attacker to exhaust resources on the affected device, causing the device to reload.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02466 84th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
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
CiscoCisco Firepower Threat Defense Softwareall versions—No fix listedCNA
  • Cisco Firepower Threat Defense Software VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 7

CPEVersionsRoleVendor
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.14.0:*:*:*:*:*:*:*2.9.14.0VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.15:*:*:*:*:*:*:*2.9.15VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.16:*:*:*:*:*:*:*2.9.16VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.17:*:*:*:*:*:*:*2.9.17VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*before 6.4.0.12; 6.5.0 to before 6.6.3; 6.7.0 to before 6.7.0.2VulnerableCisco
cpe:2.3:a:cisco:unified_threat_defense:*:*:*:*:*:*:*:*16.12 to before 16.12.6; 17.3 to before 17.3.4a; 17.4 to before 17.4.2VulnerableCisco
cpe:2.3:a:snort:snort:*:*:*:*:*:*:*:*2.0.0 to before 2.9.18VulnerableSnort
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.14.0:*:*:*:*:*:*:* Versions 2.9.14.0 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.15:*:*:*:*:*:*:* Versions 2.9.15 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.16:*:*:*:*:*:*:* Versions 2.9.16 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.17:*:*:*:*:*:*:* Versions 2.9.17 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:* Versions before 6.4.0.12; 6.5.0 to before 6.6.3; 6.7.0 to before 6.7.0.2 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:unified_threat_defense:*:*:*:*:*:*:*:* Versions 16.12 to before 16.12.6; 17.3 to before 17.3.4a; 17.4 to before 17.4.2 Vulnerable ·Cisco
  • cpe:2.3:a:snort:snort:*:*:*:*:*:*:*:* Versions 2.0.0 to before 2.9.18 Vulnerable ·Snort

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-40114
  2. 2026-10-03 Alias added: GHSA-5v43-2p8q-45m6

References

Advisory 2

Other 1

  • TI-2026-16344 Cisco Secure Firewall Management Center Software Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 10.0
  • TI-2026-16292 Cisco Secure Firewall Management Center Authentication Bypass Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 10.0
  • TI-2026-16502 Cisco Secure Firewall Management Center Software Static Credential Vulnerability KEVCVSS 3.1MEDIUM 5.3
  • TI-2016-05515 The Threat Management Console in Cisco Firepower Management Center 5.2.0 through 6.0.1… CVSS 3.1HIGH 8.8
  • TI-2025-14563 Cisco Secure Firewall Management Center Software Radius Remote Code Execution Vulnerability CVSS 3.1CRITICAL 10.0
  • TI-2023-06757 Improper privilege management in Cisco Firepower Management Center CVSS 3.1CRITICAL 9.9
See all 186 →

Sources

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