8.6

CVE-2026-20230: Cisco Unified Communications Manager Server-Side Request Forgery (SSRF) Vulnerability

CVSS: 8.6v3.1HighKEVAnalyzed
Published 03-06-2026Last modified 07-10-2026
Open JSON

Vulnerability summary

CVE-2026-20230 is a high (CVSS 8.6) Server-Side Request Forgery (SSRF) vulnerability in Cisco Unified Communications Manager. It is known to be exploited: CISA lists it, first on 25-06-2026. EPSS estimates a 88.20% chance of exploitation in the next 30 days, higher than 99.7% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
85/100
0100
Critical · default modelHow is this calculated?
CVSS score
8.6/10
010
High · v3.1 (CVE.org)
EPSS score
88.20%
0%100%
Critical · 0.00 pp in 30 days
KEVListedCISA
RansomwareNone recordedNo known use recorded
Public exploits1reference

Timeline

  1. 03-06-2026
    PublishedVulnerability first disclosed.
  2. 25-06-2026
    Added to CISA KEVCisco Unified Communications Manager Server-Side Request Forgery (SSRF) Vulnerability
  3. 28-06-2026
    CISA remediation dueApply mitigations per vendor instructions.
  4. 07-10-2026
    Last modifiedVulnerability information updated.

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 metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

88.20%

Chance of exploitation in the next 30 days

Percentile

100%

Versus all other CVEs

30-day change

0.00 pp

From 88.20% on 21-09-2026

21-09-202621-10-2026
EPSS score
88.20%

Known exploited

Compare KEV catalogs
CISA KEVListed
Added
25-06-2026
Federal due date
28-06-2026

CISA required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. www.cisco.com/c/en/us/support/docs/csa/cisco-sa-cucm-ssrf-cXPnHcW.html nvd.nist.gov/vuln/detail/CVE-2026-20230

Public exploits

1 found
  • referenceUnverified

    Exploit Reference (denizhalil.com)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Cisco2 products
  • cisco unified communications manager14 | 14SU1 | 14SU2 | 14SU3 | 15 | 15SU1 | 14SU4 | 14SU4a | 15SU1a | 15SU2 | 15.0.1.13010-1 | 15.0.1.13011-1 | 15.0.1.13012-1 | 15.0.1.13013-1 | 15.0.1.13014-1 | 15.0.1.13015-1 | 15.0.1.13016-1 | 15.0.1.13017-1 | 15SU3a | 14SU5 | 15SU4 | 15SU4a
  • unified_communications_manager≥ 14.0, < 14su6 | ≥ 15.0, ≤ 15su4a

1 vendor · 2 products

References

3 links