Cyber Resilience

CVE-2024-20294

Cisco Nx-Os 10.1\(1\) … 9.3\(9\)

Published
29 February 2024
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 6.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:H
EPSS Score 0.0032 24th percentile
Risk Priority 48 floored blend · peak EPSS

Summary

CVE-2024-20294 is a medium-severity Buffer Access with Incorrect Length Value (CWE-805) vulnerability in Cisco Nx-Os. Its CVSS base score is 6.6 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 24th 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 Link Layer Discovery Protocol (LLDP) feature of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due…

more

to improper handling of specific fields in an LLDP frame. An attacker could exploit this vulnerability by sending a crafted LLDP packet to an interface of an affected device and having an authenticated user retrieve LLDP statistics from the affected device through CLI show commands or Simple Network Management Protocol (SNMP) requests. A successful exploit could allow the attacker to cause the LLDP service to crash and stop running on the affected device. In certain situations, the LLDP crash may result in a reload of the affected device. Note: LLDP is a Layer 2 link protocol. To exploit this vulnerability, an attacker would need to be directly connected to an interface of an affected device, either physically or logically (for example, through a Layer 2 Tunnel configured to transport the LLDP protocol).

CWE(s)

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.
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.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-20202Same vendor: Cisco
CVE-2025-20169Same vendor: Cisco
CVE-2025-20175Same vendor: Cisco
CVE-2025-20174Same vendor: Cisco
CVE-2025-20170Same vendor: Cisco
CVE-2024-20399Same product: Cisco Mds 9132T
CVE-2023-20168Same product: Cisco Mds 9132T
CVE-2023-20049Same vendor: Cisco
CVE-2023-20169Same product: Cisco Nexus 3048
CVE-2024-20285Same product: Cisco Nexus 3016

Affected Assets

cisco
firepower extensible operating system
2.10.1.159, 2.10.1.166, 2.10.1.179, 2.10.1.207, 2.10.1.234
cisco
nx-os
10.1\(1\), 10.1\(2\), 10.1\(2t\), 10.2\(1\), 10.2\(1q\)
cisco
unified computing system
3.1\(1e\), 3.1\(1g\), 3.1\(1h\), 3.1\(1k\), 3.1\(1l\)

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

Developer testing and evaluation (including fuzzing and static analysis) directly finds incorrect length values used in sequential buffer accesses.

Secure engineering principles require explicit bounds checking and correct length calculations when performing buffer operations.

Input validation rejects or corrects malformed length values supplied from external sources before they reach buffer operations.

Memory protection mechanisms limit the blast radius when an incorrect length value causes an out-of-bounds access.

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 prevent incorrect-length buffer operations via safe APIs, reviews, and testing.

ID.RA-01 partial match
prevents

Vulnerability identification can discover buffer-length flaws but does not prevent their introduction.

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.

finds

Security testing in development can detect out-of-bounds accesses, but does not guarantee prevention.

prevents

Secure development life cycle mandates buffer-safety practices that directly prevent incorrect length values.

prevents

Application security requirements can specify buffer-size validation, but do not prescribe implementation details.

prevents

Secure architecture principles encourage bounds-checked APIs, yet leave concrete coding decisions to developers.

prevents

Secure coding explicitly requires correct buffer-length handling, eliminating CWE-805 when followed.

References