CVE-2026-20045
Cisco Unified Communications Products Code Injection Vulnerability
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 11 February 2026). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
Description
A vulnerability in Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unity Connection, and Cisco Webex Calling Dedicated Instance could allow an unauthenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. This vulnerability is due to improper validation of user-supplied input in HTTP requests. An attacker could exploit this vulnerability by sending a sequence of crafted HTTP requests to the web-based management interface of an affected device. A successful exploit could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to root. Note: Cisco has assigned this security advisory a Security Impact Rating (SIR) of Critical rather than High as the score indicates. The reason is that exploitation of this vulnerability could result in an attacker elevating privileges to root.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 4.48% probability · 91th percentile
- CISA KEV
- Listed 21 January 2026 · due 11 February 2026
- Weakness
- CWE-94
- Affected
- cisco/unified communications manager · cisco/unified communications manager im and presence service · cisco/unity connection
- Source
- psirt@cisco.com
CISA notes
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voice-rce-mORhqY4b ; https://nvd.nist.gov/vuln/detail/CVE-2026-20045
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.