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Known Exploited Vulnerability
8.2
HIGH CVSS 3.1
CVE-2026-20045
Cisco Unified Communications Products Code Injection Vulnerability - [Actively Exploited]
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.

INFO

Published Date :

Jan. 21, 2026, 5:16 p.m.

Last Modified :

Jan. 21, 2026, 9:16 p.m.

Remotely Exploit :

Yes !

Source :

[email protected]
CISA Notification
CISA KEV (Known Exploited Vulnerabilities)

For the benefit of the cybersecurity community and network defenders—and to help every organization better manage vulnerabilities and keep pace with threat activity—CISA maintains the authoritative source of vulnerabilities that have been exploited in the wild.

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.

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.

Notes :

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voice-rce-mORhqY4b ; https://nvd.nist.gov/vuln/detail/CVE-2026-20045

Affected Products

The following products are affected by CVE-2026-20045 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Cisco unified_communications_manager_im_and_presence_service
2 Cisco unified_communications_manager
3 Cisco unity_connection
: Total Affected Vendor : 1 | Products : 3
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Apply vendor patches to Cisco Unified Communications products to fix command execution vulnerability.
  • Apply Cisco security updates for Unified CM products.
  • Update Unified CM SME to the latest version.
  • Install patches for Unified CM IM&P.
  • Upgrade Cisco Unity Connection and Webex Calling.
Public PoC/Exploit Available at Github

CVE-2026-20045 has a 1 public PoC/Exploit available at Github. Go to the Public Exploits tab to see the list.

References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-20045.

URL Resource
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voice-rce-mORhqY4b
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20045
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-20045 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-20045 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

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Updated: 6 hours, 55 minutes ago
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Born at : Dec. 10, 2020, 6:50 a.m. This repo has been linked 1 different CVEs too.

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-20045 vulnerability anywhere in the article.

  • The Hacker News
Cisco Fixes Actively Exploited Zero-Day CVE-2026-20045 in Unified CM and Webex

Cisco has released fresh patches to address what it described as a "critical" security vulnerability impacting multiple Unified Communications (CM) products and Webex Calling Dedicated Instance that i ... Read more

Published Date: Jan 22, 2026 (1 hour, 8 minutes ago)
  • Daily CyberSecurity
CVE-2025-15521 (CVSS 9.8): Critical Academy LMS Flaw Exploited for Admin Takeover

A critical security vulnerability has been unearthed in the Academy LMS plugin for WordPress, a popular tool used by thousands of educators to sell courses and build eLearning platforms. The flaw, tra ... Read more

Published Date: Jan 22, 2026 (1 hour, 19 minutes ago)
  • CybersecurityNews
Cisco Unified Communications 0-day RCE Vulnerability Exploited in the Wild to Gain Root Access

Cisco has disclosed a critical zero-day remote code execution (RCE) vulnerability, CVE-2026-20045, actively exploited in the wild. Affecting key Unified Communications products, this flaw allows unaut ... Read more

Published Date: Jan 22, 2026 (1 hour, 42 minutes ago)
  • Daily CyberSecurity
Under Attack: Critical Cisco RCE (CVE-2026-20045) Exploited in the Wild

Cisco has issued an urgent warning to network administrators worldwide: a critical remote code execution (RCE) vulnerability affecting its core communications software is currently being targeted by h ... Read more

Published Date: Jan 22, 2026 (2 hours, 34 minutes ago)
  • Daily CyberSecurity
New Campaign Targets FortiGate Firewalls with Unauthorized Config Changes

A fresh wave of automated cyberattacks is targeting FortiGate firewalls, exploiting unauthorized access to create backdoors and steal sensitive configuration data. Security researchers at Arctic Wolf ... Read more

Published Date: Jan 22, 2026 (3 hours, 1 minute ago)
  • Daily CyberSecurity
CVE-2025-13878: High-Severity BIND Flaw Exposes Servers to Remote Crash

The Internet Systems Consortium (ISC) has issued a high-severity security advisory for BIND 9, the software that powers a vast portion of the internet’s Domain Name System (DNS) infrastructure. A newl ... Read more

Published Date: Jan 22, 2026 (3 hours, 22 minutes ago)
  • TheCyberThrone
CVE-2026-20045: Cisco Unified Communications Zero-Day Under Active Attack

January 22, 2026Cisco recently patched a critical code injection vulnerability in its Unified Communications suite, tracked as CVE-2026-20045, which attackers are already exploiting in the wild. This ... Read more

Published Date: Jan 22, 2026 (4 hours, 7 minutes ago)
  • BleepingComputer
Cisco fixes Unified Communications RCE zero day exploited in attacks

Cisco has fixed a critical Unified Communications and Webex Calling remote code execution vulnerability, tracked as CVE-2026-20045, that has been actively exploited as a zero-day in attacks. Tracked a ... Read more

Published Date: Jan 21, 2026 (6 hours, 58 minutes ago)
  • Help Net Security
RCE flaw in Cisco enterprise communications products probed by attackers (CVE-2026-20045)

Cisco has fixed a critical remote code execution vulnerability (CVE-2026-20045) in some of its unified communications solutions that’s being targeted by attackers in the wild, the company announced on ... Read more

Published Date: Jan 21, 2026 (10 hours, 59 minutes ago)

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-20045 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jan. 21, 2026

    Action Type Old Value New Value
    Added Reference https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20045
  • New CVE Received by [email protected]

    Jan. 21, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
    Added CWE CWE-94
    Added Reference https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-voice-rce-mORhqY4b
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 8.2
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact