Cyber Resilience

CVE-2024-20330

Memory Safety in Cisco Secure Firewall Threat Defense 7.0.0.0 … 7.4.2

Memory Safety
Published
23 October 2024
Modified
11 August 2026
Patch / advisory
View advisory
CVSS Score v3.1 8.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS Score 0.0066 48th percentile
Risk Priority 63 floored blend · peak EPSS

Summary

CVE-2024-20330 is a high-severity Access of Memory Location After End of Buffer (CWE-788) vulnerability in Cisco Secure Firewall Threat Defense. Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 48th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

A vulnerability in the Snort 2 and Snort 3 TCP and UDP detection engine of Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 2100 Series Appliances could allow an unauthenticated, remote attacker to cause memory corruption, which could cause…

more

the Snort detection engine to restart unexpectedly. This vulnerability is due to improper memory management when the Snort detection engine processes specific TCP or UDP packets. An attacker could exploit this vulnerability by sending crafted TCP or UDP packets through a device that is inspecting traffic using the Snort detection engine. A successful exploit could allow the attacker to restart the Snort detection engine repeatedly, which could cause a denial of service (DoS) condition. The DoS condition impacts only the traffic through the device that is examined by the Snort detection engine. The device can still be managed over the network. Note: Once a memory block is corrupted, it cannot be cleared until the Cisco Firepower 2100 Series Appliance is manually reloaded. This means that the Snort detection engine could crash repeatedly, causing traffic that is processed by the Snort detection engine to be dropped until the device is manually reloaded.

CWE(s)
CWE-788

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-20006Same product: Cisco Firepower 2110
CVE-2024-20402Same product: Cisco Secure Firewall Threat Defense
CVE-2023-20244Same product: Cisco Firepower 2110
CVE-2023-20169Same vendor: Cisco
CVE-2024-20408Same product: Cisco Secure Firewall Threat Defense
CVE-2026-20022Same product: Cisco Secure Firewall Threat Defense
CVE-2024-20494Same product: Cisco Secure Firewall Threat Defense
CVE-2026-20049Same product: Cisco Secure Firewall Threat Defense
CVE-2025-20333Same product: Cisco Secure Firewall Threat Defense
CVE-2026-20100Same product: Cisco Secure Firewall Threat Defense

Affected Assets

cisco
secure firewall threat defense
7.0.0.0, 7.0.0.1, 7.0.1, 7.0.1.1, 7.0.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.4.1

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover buffer-end violations through static analysis, fuzzing, or dynamic bounds checks.

SA-8 Security and Privacy Engineering Principles partial match

Security engineering principles require bounds checking, safe arithmetic, and language choices that structurally eliminate post-end buffer accesses.

SI-10 Information Input Validation partial match

Input validation enforces bounds on lengths and indices before buffer operations, stopping out-of-bounds accesses after the end of the buffer.

SI-16 Memory Protection partial match

Memory protection mechanisms limit the effects of post-end buffer accesses by blocking unauthorized code execution or data corruption.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require bounds checking and input validation that prevent out-of-bounds buffer accesses.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development can detect buffer-overrun defects before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle includes buffer-handling practices that reduce out-of-bounds accesses.

A.8.26 Application security requirements partial match
prevents

Application security requirements can mandate bounds checking and safe memory APIs.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles discourage unsafe pointer arithmetic and unbounded buffers.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly forbid writing or reading past buffer ends.

References