High severity · published Jun 3, 2026
CVE-2026-20230
Cisco Unified Communications Manager Server-Side Request Forgery Vulnerability
In wildKEV
8.6
CVSS
88.2%
EPSS
Yes
On KEV
Description
A vulnerability in Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an unauthenticated, remote attacker to conduct server-side request forgery (SSRF) attacks through an affected device. This vulnerability is due to improper input validation for specific HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to write files to the underlying operating system that could be used later to elevate 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. Note: To exploit this vulnerability, the WebDialer service must be enabled. WebDialer is disabled by default.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)88.2% · higher than 100% of CVEs
Exploited in the wildYes
CISA KEVListed Jun 25, 2026
Federal remediation dueJun 28, 2026
Ransomware campaign useNot known
Affected products
Which versions
CU
Cisco Unified Communications Manager · Cisco
14; 14SU1; 14SU2; 14SU3; 15; 15SU1; +16 more · source: vendor
UC
Unified Communications Manager · Cisco
14.0 before 14su6; 14.0 before 14su6; 15.0 through 15su4a; 15.0 through 15su4a · source: NVD, KEV
In the news
VulnerabilityHigh
CISA Adds Two Known Exploited Vulnerabilities to Catalog
CISA has added two new vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog , based on evidence of active exploitation.   CVE-2026-12569 PTC Windchill and FlexPLM Improper Input Validation Vulnerability CVE-2026-20230 Cisco Unified Communications Manager Server-Side Request Forgery (SSRF) Vulnerability These types of vulnerabilities are frequent attack vectors for malicious cyber actors and pose significant risks to the federal enterprise. Binding Operational Directive (BOD) 26-04: Prioritizing Security Updates Based on Risk establishes vulnerability management requirements for Federal Civilian Executive Branch (FCEB) agencies. BOD 26-04 reinforces the importance of the KEV Catalog and requires federal agencies to prioritize rapid remediation of high-risk vulnerabilities, specifically those identified by Common Vulnerabilities and Exposures (CVEs) listed in CISA’s KEV Catalog on publicly exposed assets that grant total control of the asset post-exploitation, while deferring action for lower-risk vulnerabilities. BOD 26-04 further establishes basic expectations for when agencies must check whether threat actors compromised the system before the patch was applied. While BOD 26-04 applies only to FCEB agencies, CISA encourages all organizations to adopt risk-based vulnerability management and prioritize remediation of KEV Catalog vulnerabilities . CISA will continue to add vulnerabilities to the catalog that meet the specified criteria...
Jun 25, 2026·CISA Advisories
VulnerabilityHigh
[CISA KEV] CVE-2026-20230: Cisco Unified Communications Manager - Cisco Unified Communications Manager Server-Side Request Forgery (SSRF) Vulnerability
Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) contain a server-side request forgery (SSRF) Vulnerability that could allow an unauthenticated, remote attacker to write files to the underlying operating system that could be used later to elevate to root.
UCUnified Communications ManagerCVE-2026-20230
Jun 25, 2026·CISA KEV
VulnerabilityCritical
Cisco Unified CM Flaw CVE-2026-20230 Actively Exploited in the Wild
Attackers exploit Cisco Unified CM flaw (CVE-2026-20230) allowing unauth HTTP requests to trigger SSRF, write files, and gain root access Cisco Unified Communications Manager has a serious vulnerability, tracked as CVE-2026-20230 (CVSS score of 8.6), that attackers are already exploiting. The flaw, caused by improper validation of certain HTTP requests, allows a remote attacker without […]
Jun 24, 2026·Security Affairs
VulnerabilityHigh
Cisco Unified CM flaw actively exploited to drop webshells (CVE-2026-20230)
CVE-2026-20230, a server-side request forgery (SSRF) vulnerability affecting Cisco’s Unified Communications Manager (Unified CM), is being exploited to drop webshells and achieve remote code execution capability on the underlying server. “Our honeypots are seeing automated sweeps dropping webshells, all via Tor,” threat intelligence firm Defused warned today, after observing initial attacks over the weekend. “The observed chain abuses the WebDialer SSRF to deploy a rogue Apache Axis service, uses that service to write a first-stage … More → The post Cisco Unified CM flaw actively exploited to drop webshells (CVE-2026-20230) appeared first on Help Net Security .
Jun 24, 2026·Help Net Security
VulnerabilityHigh
Cisco Unified CM Flaw Exploited After PoC Reveals File-Write Path to Root
Threat actors have begun to exploit a recently disclosed critical security flaw impacting Cisco Unified Communications Manager (Unified CM) and Unified Communications Manager Session Management Edition (Unified CM SME). The vulnerability, tracked as CVE-2026-20230 (CVSS score: 8.6), is a case of improper input validation for specific HTTP requests that could allow an unauthenticated, remote
Jun 24, 2026·The Hacker News
VulnerabilityHigh
Cisco Unified CM flaw CVE-2026-20230 now exploited in attacks
A high-severity SSRF vulnerability, tracked as CVE-2026-20230, in Cisco Unified Communications Manager Server is now being exploited in attacks. [...]
Jun 23, 2026·BleepingComputer
Affected product
CU
Cisco Unified Communications Manager
Cisco
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