CVE-2026-20045 | Cisco Unified Communications Products Remote Code Execution Vulnerability

Exp

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.

Published: 2026-01-21 Last update: 2026-02-13 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-20045 is rated Critical Active Threat (87.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 3.03%). CISA KEV confirms active exploitation (added 2026-01-21) affecting Cisco / Unified Communications Manager. a weakness (CWE-94) Unauthenticated remote administrative access may be possible. The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2026-20045

Name: Cisco Unified Communications Products Code Injection Vulnerability · CISA KEV detail

Exploit added: 2026-01-21

Action due: 2026-02-11

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.

Exploit prediction scoring system (EPSS) score for CVE-2026-20045

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-08 3.71% 3.03% -0.68%
2 2026-06-07 3.02% 3.71% +0.69%
3 2026-06-05 — 3.02% —

Full EPSS history (20 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-20045

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.2 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 4.2 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]

Weakness enumeration for CVE-2026-20045

Affected software / configurations for CVE-2026-20045

Vendor Product Version Raw CPE
cisco unified_communications_manager >= 12.5, < 14su5 cpe:2.3:a:cisco:unified_communications_manager:*:*:*:*:-:*:*:*
cisco unified_communications_manager >= 12.5, < 14su5 cpe:2.3:a:cisco:unified_communications_manager:*:*:*:*:session_management:*:*:*
cisco unified_communications_manager >= 15.0, <= 15su3a cpe:2.3:a:cisco:unified_communications_manager:*:*:*:*:-:*:*:*
cisco unified_communications_manager >= 15.0, <= 15su3a cpe:2.3:a:cisco:unified_communications_manager:*:*:*:*:session_management:*:*:*
cisco unified_communications_manager_im_and_presence_service >= 12.5, < 14su5 cpe:2.3:a:cisco:unified_communications_manager_im_and_presence_service:*:*:*:*:*:*:*:*
cisco unified_communications_manager_im_and_presence_service >= 15.0, <= 15su3a cpe:2.3:a:cisco:unified_communications_manager_im_and_presence_service:*:*:*:*:*:*:*:*
cisco unity_connection >= 12.5, < 14su5 cpe:2.3:a:cisco:unity_connection:*:*:*:*:*:*:*:*
cisco unity_connection >= 15.0, <= 15su3 cpe:2.3:a:cisco:unity_connection:*:*:*:*:*:*:*:*

References for CVE-2026-20045

cvelogic Threat Intelligence