CVE-2024-20375

A vulnerability in the SIP call processing function of Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper parsing of SIP messages. An attacker could exploit this vulnerability by sending a crafted SIP message to an affected Cisco Unified CM or Cisco Unified CM SME device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition that interrupts the communications of reliant voice and video devices.

Published: 2024-08-21 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-20375 is rated Moderate Risk (51.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.74%). 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-2024-20375

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 2026-06-15 0.96% 0.74% -0.22%
2 2025-11-21 0.71% 0.96% +0.26%
3 2025-11-18 — 0.71% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-20375

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.6 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/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:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
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 4.0 [email protected]
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-2024-20375

Affected software / configurations for CVE-2024-20375

Vendor Product Version Raw CPE
cisco unified_communications_manager 12.0\(1\)su1 cpe:2.3:a:cisco:unified_communications_manager:12.0\(1\)su1:*:*:*:*:*:*:*
cisco unified_communications_manager 12.0\(1\)su2 cpe:2.3:a:cisco:unified_communications_manager:12.0\(1\)su2:*:*:*:*:*:*:*
cisco unified_communications_manager 12.0\(1\)su3 cpe:2.3:a:cisco:unified_communications_manager:12.0\(1\)su3:*:*:*:*:*:*:*
cisco unified_communications_manager 12.0\(1\)su4 cpe:2.3:a:cisco:unified_communications_manager:12.0\(1\)su4:*:*:*:*:*:*:*
cisco unified_communications_manager 12.0\(1\)su5 cpe:2.3:a:cisco:unified_communications_manager:12.0\(1\)su5:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\) cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\):*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su1 cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su1:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su2 cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su2:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su3 cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su3:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su4 cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su4:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su5 cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su5:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su6 cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su6:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su7 cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su7:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su7a cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su7a:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su8 cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su8:*:*:*:*:*:*:*
cisco unified_communications_manager 12.5\(1\)su8a cpe:2.3:a:cisco:unified_communications_manager:12.5\(1\)su8a:*:*:*:*:*:*:*

References for CVE-2024-20375

cvelogic Threat Intelligence