How severe is CVE-2024-20375?

CVE-2024-20375 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2024-20375 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-20375?

CVE-2024-20375 primarily affects Cisco Unified Communications Manager. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2024-20375?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2024-20375 have an EU (EUVD) identifier?

Yes. CVE-2024-20375 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18090.

When was CVE-2024-20375 published?

CVE-2024-20375 was published on 2024-08-21 and last updated on 2026-06-17.

CVE-2024-20375

CVE-2024-20375 is a high-severity vulnerability in Cisco Unified Communications Manager with a CVSS 3.x base score of 8.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 8.6)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-18090
Weakness: CWE-787
Affected product: Cisco Unified Communications Manager
Published: 2024-08-21
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2024-20375?: CVE-2024-20375 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2024-20375 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-20375?: CVE-2024-20375 primarily affects Cisco Unified Communications Manager. In total, 16 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2024-20375?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2024-20375 have an EU (EUVD) identifier?: Yes. CVE-2024-20375 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18090.
When was CVE-2024-20375 published?: CVE-2024-20375 was published on 2024-08-21 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-dos-kkHq43We

Affected products (16)

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

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