Reference page — cumulative record through Wednesday, October 7, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
CVE-2026-20045
Cisco Unified Communications Products Remote Code Execution Vulnerability
AV AC PR UI S C I A CVSS EPSS %ile KEV
N L N N U H L N 8.2 .0454 91.3 YES
AFFECTED
Product Versions Fixed
Cisco Unified Communications Manager 12.5(1)SU2 – —
Cisco Unified Communications Manager IM and Presence Service 12.5(1) – —
Cisco Unity Connection 12.5(1) – —
TIMELINE
Oct 8 Reserved by cisco
Jan 21 Added to CISA KEV, remediation due 2026-02-11
Jan 21 Published (CNA: cisco)
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.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| October 8, 2025 | Reserved | Reserved by cisco |
| January 21, 2026 | KEV ADDED | Added to CISA KEV, remediation due 2026-02-11 |
| January 21, 2026 | Published | Published (CNA: cisco) |
Affected
Affected products and packages — 3 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Cisco | Cisco Unified Communications Manager | — | 12.5(1)SU2 | — |
| Cisco | Cisco Unified Communications Manager IM and Presence Service | — | 12.5(1) | — |
| Cisco | Cisco Unity Connection | — | 12.5(1) | — |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-20045 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, October 7, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.