CVE-2026-20045
Published: January 21, 2026
Official Description
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 contain a code injection vulnerability that could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to root.
CISA KEV Advisory
Cisco Unified Communications Products Code Injection Vulnerability
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 contain a code injection vulnerability that could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to root.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Risk Analysis
This critical code injection vulnerability in Cisco Unified Communications Manager and related products allows an attacker to gain user-level access to the underlying operating system and then elevate privileges to root. With a CVSS score of 9.8 and confirmed in-the-wild exploitation, this is an extremely urgent and remotely exploitable threat.
This vulnerability is actively exploited in the wild and is included in CISA's Known Exploited Vulnerabilities catalog. It is remotely exploitable with low attack complexity.
Immediately apply all available security updates for Cisco Unified Communications Manager, Unified CM SME, Unified CM IM&P, Unity Connection, and Webex Calling Dedicated Instance. Restrict network access to these systems and monitor for suspicious activity.
Technical Analysis
CVE-2026-20045 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.
CISA has added CVE-2026-20045 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (2)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-20045 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1