Security Resilience

CVE-2023-20155

DoS in Cisco Secure Firewall Management Center 6.2.3 – 6.2.3.18

Published
01 November 2023
Modified
26 November 2024
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0067 51th percentile
Risk Priority 58 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-20155 is a high-severity Allocation of Resources Without Limits or Throttling (CWE-770) vulnerability in Cisco Secure Firewall Management Center. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique OS Exhaustion Flood (T1499.001); ranked in the top 49% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability Data

A vulnerability in a logging API in Cisco Firepower Management Center (FMC) Software could allow an unauthenticated, remote attacker to cause the device to become unresponsive or trigger an unexpected reload. This vulnerability could also allow an attacker with valid…

more

user credentials, but not Administrator privileges, to view a system log file that they would not normally have access to. This vulnerability is due to a lack of rate-limiting of requests that are sent to a specific API that is related to an FMC log. An attacker could exploit this vulnerability by sending a high rate of HTTP requests to the API. A successful exploit could allow the attacker to cause a denial of service (DoS) condition due to the FMC CPU spiking to 100 percent utilization or to the device reloading. CPU utilization would return to normal if the attack traffic was stopped before an unexpected reload was triggered.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499.001 OS Exhaustion Flood Impact
Adversaries may launch a denial of service (DoS) attack targeting an endpoint's operating system (OS).
T1499.002 Service Exhaustion Flood Impact
Adversaries may target the different network services provided by systems to conduct a denial of service (DoS).
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
T1001.003 Protocol or Service Impersonation Command And Control
Adversaries may impersonate legitimate protocols or web service traffic to disguise command and control activity and thwart analysis efforts.
T1003 OS Credential Dumping Credential Access
Adversaries may attempt to dump credentials to obtain account login and credential material, normally in the form of a hash or a clear text password.
T1005 Data from Local System Collection
Adversaries may search local system sources, such as file systems, configuration files, local databases, virtual machine files, or process memory, to find files of interest and sensitive data prior to Exfiltration.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-20219Same product: Cisco Secure Firewall Management Center
CVE-2023-20114Same product: Cisco Secure Firewall Management Center
CVE-2020-3569Same vendor: Cisco
CVE-2020-3566Same vendor: Cisco
CVE-2023-20206Same product: Cisco Secure Firewall Management Center
CVE-2023-20041Same product: Cisco Secure Firewall Management Center
CVE-2023-20220Same product: Cisco Secure Firewall Management Center
CVE-2023-20074Same product: Cisco Secure Firewall Management Center
CVE-2023-20005Same product: Cisco Secure Firewall Management Center
CVE-2023-20047Same vendor: Cisco

Affected Assets

cisco
secure firewall management center
6.2.3 — 6.2.3.18 · 6.4.0 — 6.4.0.16 · 6.6.0 — 6.6.7.1

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

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Detect
Catch it (NIST detect / respond)

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Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

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Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-400 CWE-770

Limiting concurrent sessions directly prevents uncontrolled resource consumption by capping the number of active sessions per user or account.

addresses: CWE-400 CWE-770

Contingency plan testing includes resource exhaustion scenarios to verify recovery, making it harder for attackers to sustain exploits that cause uncontrolled consumption.

addresses: CWE-400 CWE-770

Updated contingency plans include current procedures to detect, contain, and recover from resource exhaustion, limiting an attacker's ability to sustain impact from uncontrolled consumption.

addresses: CWE-400 CWE-770

Alternate site allows resumption of operations if resource exhaustion at the primary site is exploited to cause unavailability.

addresses: CWE-400 CWE-770

Alternate telecommunications services enable resumption of essential functions when primary services become unavailable due to uncontrolled resource consumption.

addresses: CWE-400 CWE-770

Planning and coordination of security activities (scans, tests, maintenance) directly imposes scheduling and throttling that prevents those activities from producing uncontrolled resource consumption.

addresses: CWE-400 CWE-770

Performance metrics and monitoring inherently track resource consumption patterns, making uncontrolled consumption easier to detect and mitigate.

addresses: CWE-400 CWE-770

Terminating idle connections bounds resource consumption that would otherwise allow uncontrolled accumulation of open sessions.

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.IR-04 partial match
blocks

Monitoring capacity and taking action to maintain availability directly reduces unchecked resource allocation.

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.

removes
removes
removes
removes
finds

Pre-agreed severity-based prioritization and resource allocation during incident triage reduce the likelihood that an attacker-induced resource exhaustion will overwhelm the organization before corrective action is taken.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-248552 OL 8 must be configured so that all network connections associated with SSH traffic terminate after becoming unresponsive. blocks CWE-770
  • V-248553 OL 8 must be configured so that all network connections associated with SSH traffic are terminated after 10 minutes of becoming unresponsive. blocks CWE-770
Oracle Linux 9 (2 rules)
  • V-271710 OL 9 must be configured so that all network connections associated with SSH traffic are terminated after 10 minutes of becoming unresponsive. blocks CWE-770
  • V-271709 OL 9 must be configured so that all network connections associated with SSH traffic terminate after becoming unresponsive. blocks CWE-770
RHEL 8 (1 rule)
  • V-230244 RHEL 8 must be configured so that all network connections associated with SSH traffic terminate after becoming unresponsive. blocks CWE-770

References