CVEs / CVE-2026-20045
CVE-2026-20045: Cisco Unified Communications Products Code Injection Vulnerability
- Known exploited in the CISA KEV catalog since 21 Jan 2026
- critical 9.8 CVSS 3.1 (NVD)
- EPSS 4.54% chance of exploitation in the next 30 days, higher than 91% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
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.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Cisco Cisco Unified Communications Manager | 12.5(1)SU2 | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU1 | — |
| Cisco Cisco Unified Communications Manager | 12.5(1) | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU3 | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU4 | — |
| Cisco Cisco Unified Communications Manager | 14 | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU5 | — |
| Cisco Cisco Unified Communications Manager | 14SU1 | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU6 | — |
| Cisco Cisco Unified Communications Manager | 14SU2 | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU7 | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU7a | — |
| Cisco Cisco Unified Communications Manager | 14SU3 | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU8 | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU8a | — |
| Cisco Cisco Unified Communications Manager | 15 | — |
| Cisco Cisco Unified Communications Manager | 15SU1 | — |
| Cisco Cisco Unified Communications Manager | 14SU4 | — |
| Cisco Cisco Unified Communications Manager | 14SU4a | — |
| Cisco Cisco Unified Communications Manager | 15SU1a | — |
| Cisco Cisco Unified Communications Manager | 12.5(1)SU9 | — |
| Cisco Cisco Unified Communications Manager | 15SU2 | — |
| Cisco Cisco Unified Communications Manager | 15.0.1.13010-1 | — |
| Cisco Cisco Unified Communications Manager | 15.0.1.13011-1 | — |
| Cisco Cisco Unified Communications Manager | 15.0.1.13012-1 | — |
| Cisco Cisco Unified Communications Manager | 15.0.1.13013-1 | — |
| Cisco Cisco Unified Communications Manager | 15.0.1.13014-1 | — |
| Cisco Cisco Unified Communications Manager | 15.0.1.13015-1 | — |
| Cisco Cisco Unified Communications Manager | 15.0.1.13016-1 | — |
| Cisco Cisco Unified Communications Manager | 15.0.1.13017-1 | — |
Exploitation
| In CISA KEV since | 21 Jan 2026 |
|---|---|
| Due date for US federal agencies | 11 Feb 2026 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-94 |
References
- CVE-2026-20045 on NVD
- CVE-2026-20045 in the CISA KEV catalog
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voice-rce-mORhqY4b (cited by CISA)
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voice-rce-mORhqY4b Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20045 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.