Cyber Resilience

CVE-2023-20020

DoS in Cisco Broadworks Application Delivery Platform Device Management 22.0 – 2022.11_1.273

DoS
Published
20 January 2023
Modified
21 November 2024
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 0.0086 55th percentile
Risk Priority 63 floored blend · peak EPSS

Summary

CVE-2023-20020 is a high-severity Infinite Loop (CWE-835) vulnerability in Cisco Broadworks Application Delivery Platform Device Management. Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked in the top 45% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

A vulnerability in the Device Management Servlet application of Cisco BroadWorks Application Delivery Platform and Cisco BroadWorks Xtended Services Platform could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability…

more

is due to improper input validation when parsing HTTP requests. An attacker could exploit this vulnerability by sending a sustained stream of crafted requests to an affected device. A successful exploit could allow the attacker to cause all subsequent requests to be dropped, resulting in a DoS condition.

CWE(s)
CWE-835CWE-20

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
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 →
T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
attack.mitre.org →
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.
attack.mitre.org →
T1036.001 Invalid Code Signature Stealth
Adversaries may attempt to mimic features of valid code signatures to increase the chance of deceiving a user, analyst, or tool.
attack.mitre.org →
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2017-12234Same vendor: Cisco
CVE-2026-20153Same vendor: Cisco
CVE-2024-20394Same vendor: Cisco
CVE-2024-20327Same vendor: Cisco
CVE-2017-3881Same vendor: Cisco
CVE-2017-12235Same vendor: Cisco
CVE-2024-20406Same vendor: Cisco
CVE-2018-0159Same vendor: Cisco
CVE-2026-20224Same vendor: Cisco
CVE-2019-1821Same vendor: Cisco

Affected Assets

cisco
broadworks application delivery platform device management
22.0 — 2022.11_1.273
cisco
broadworks xtended services platform
22.0 — 23.0.1075.ap384245

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)
  • 6 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.

CP-7 Alternate Processing Site
addresses: CWE-835

Enables transfer to alternate site if an infinite loop at the primary renders processing unavailable.

PM-14 Testing, Training, and Monitoring
addresses: CWE-20

Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.

SA-11 Developer Testing and Evaluation
addresses: CWE-20

Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.

SC-5 Denial-of-service Protection
addresses: CWE-835

Detects and mitigates infinite loops that produce sustained resource consumption.

SI-10 Information Input Validation
addresses: CWE-20

Directly implements checks on information inputs to reject invalid data before processing.

SI-8 Spam Protection
addresses: CWE-20

Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.

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 (reviews, testing, static analysis) directly prevent introduction of infinite-loop defects.

ID.RA-01 partial match
prevents

Static analysis and vuln scanning during asset assessment can detect unreachable loop exits.

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 can uncover infinite-loop conditions before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates practices that can detect and prevent infinite-loop defects.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify loop-termination rules, indirectly reducing the weakness.

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

Security-by-design principles explicitly call for data validation and sanitization at every layer, reducing the chance that malformed or malicious input will be processed without scrutiny.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly address loop termination and prevent infinite loops.

A.8.32 Change management none match
none

Change management can require review of loop logic when code is modified.

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` (authoritative rows only; rows rated `none` are excluded).

RHEL 8 (1 rule)
  • V-230265 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-20

References