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CVE-2024-20339

Cisco Firepower Threat Defense Software for Firepower 2100 Series TLS Denial of Service Vulnerability

HIGH
7.5
CVSS Score
Published: October 23, 2024 at 05:09 PM UTC
Updated: August 11, 2026 at 07:40 PM UTC
2 products affected across 1 vendorSecure Firewall Threat DefenseFirepower Threat Defense

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Severity
HIGH7.5
Exploit prediction
EPSS 0.7%
SSVC
No known exploit

Description

A vulnerability in the TLS processing feature of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to an issue that occurs when TLS traffic is processed. An attacker could exploit this vulnerability by sending certain TLS traffic over IPv4 through an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition and impacting traffic to and through the affected device.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Secure Firewall Threat Defense· Cisco
95%
6.2.36.2.3.16.2.3.106.2.3.116.2.3.126.2.3.136.2.3.146.2.3.156.2.3.166.2.3.176.2.3.186.2.3.26.2.3.36.2.3.46.2.3.56.2.3.66.2.3.76.2.3.86.2.3.96.4.06.4.0.16.4.0.106.4.0.116.4.0.126.4.0.136.4.0.146.4.0.156.4.0.166.4.0.176.4.0.26.4.0.36.4.0.46.4.0.56.4.0.66.4.0.76.4.0.86.4.0.96.6.06.6.0.16.6.16.6.36.6.46.6.56.6.5.16.6.5.26.6.76.6.7.16.6.7.26.7.06.7.0.16.7.0.26.7.0.37.0.07.0.0.17.0.17.0.1.17.0.27.0.2.17.0.37.0.47.0.57.0.67.0.6.17.1.07.1.0.17.1.0.37.2.07.2.0.17.2.17.2.27.2.37.2.47.2.4.17.2.57.2.5.17.2.5.27.3.07.3.17.3.1.17.3.1.2
Firepower Threat Defense· Cisco
60%
6.2.3 ≤ v ≤ 6.2.3.186.4.0 ≤ v ≤ 6.4.0.176.6.0 ≤ v ≤ 6.6.7.26.7.0 ≤ v ≤ 6.7.0.37.0.0 ≤ v ≤ 7.0.6.17.1.0 ≤ v ≤ 7.1.0.37.2.0 ≤ v ≤ 7.2.5.27.3.0 ≤ v ≤ 7.3.1.26.2.36.2.3.16.2.3.106.2.3.116.2.3.126.2.3.136.2.3.146.2.3.156.2.3.166.2.3.176.2.3.186.2.3.26.2.3.36.2.3.46.2.3.56.2.3.66.2.3.76.2.3.86.2.3.96.4.06.4.0.16.4.0.106.4.0.116.4.0.126.4.0.136.4.0.146.4.0.156.4.0.166.4.0.176.4.0.26.4.0.36.4.0.46.4.0.56.4.0.66.4.0.76.4.0.86.4.0.96.6.06.6.0.16.6.16.6.36.6.46.6.56.6.5.16.6.5.26.6.76.6.7.16.6.7.26.7.06.7.0.16.7.0.26.7.0.37.0.07.0.0.17.0.17.0.1.17.0.27.0.2.17.0.37.0.47.0.57.0.67.0.6.17.1.07.1.0.17.1.0.37.2.07.2.0.17.2.17.2.27.2.37.2.47.2.4.17.2.57.2.5.17.2.5.27.3.07.3.17.3.1.17.3.1.2

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (3)

Broken Link
Source: [email protected]
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-xss-M446vbEO
Vendor Advisory
Source: [email protected]
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-tls-dos-QXYE5Ufy
Vendor Advisory
Source: [email protected]
https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75300

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGH[email protected]
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-476

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