CVE-2025-20165 | Cisco BroadWorks SIP Denial of Service Vulnerability

A vulnerability in the SIP processing subsystem of Cisco BroadWorks could allow an unauthenticated, remote attacker to halt the processing of incoming SIP requests, resulting in a denial of service (DoS) condition. This vulnerability is due to improper memory handling for certain SIP requests. An attacker could exploit this vulnerability by sending a high number of SIP requests to an affected system. A successful exploit could allow the attacker to exhaust the memory that was allocated to the Cisco BroadWorks Network Servers that handle SIP traffic. If no memory is available, the Network Servers can no longer process incoming requests, resulting in a DoS condition that requires manual intervention to recover.

Published: 2025-01-22 Last update: 2025-08-06 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-20165 is rated Moderate Risk (61.4/100): CVSS High severity, with medium exploitation likelihood (EPSS 3.06%). Core evidence: EPSS rose +1.05% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-20165

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-04-05 2.02% 3.06% +1.05%
2 2026-03-25 3.06% 2.02% -1.05%
3 2026-03-17 3.06%

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-20165

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2025-20165

Affected software / configurations for CVE-2025-20165

Vendor Product Version Raw CPE
cisco broadworks_network_server < 2024.11 cpe:2.3:a:cisco:broadworks_network_server:*:*:*:*:release_independent:*:*:*

References for CVE-2025-20165

cvelogic Threat Intelligence