`CVE-2026-20230` Cisco Unified Communications Manager

Affected software	Cisco Unified Communications Manager
Severity	8.6 High CVSS 3.1
Weakness	Server-side request forgery (CWE-918)
Published	3 Jun 2026
Updated	7 Oct 2026

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.

Exploitation status

Exploited

Confirmed real-world exploitation.

CISA KEV listed Confirmed exploitation in the wild. Added 2026-06-25 · remediation due 2026-06-28 · ransomware use: unknown
VulnCheck KEV listed Exploitation reported in the wild. 5 citations · honeypot sightings · 1 exploit · earliest 2026-06-22.
CISA Vulnrichment exploitation: active CISA records active exploitation. Automatable: no, technical impact: total.
Indexed PoC 3 indexed, none at 5+ stars
EPSS 89% chance in 30 days A model's forecast, not a report of exploitation. Higher than 99.8% of all scored CVEs.

VulnCheck KEV

Exploitation evidence from VulnCheck Known Exploited Vulnerabilities (VulnCheck KEV), used under VulnCheck's community terms. View CVE-2026-20230 in VulnCheck (free account).

Evidence	Source	Detail	Date
Honeypot sighting	Shadowserver honeypots	Exploitation attempts seen on 1 day	2026-07-10
Reported exploitation	x.com	/defusedcyber/status/2069074520057557244	2026-06-22
Reported exploitation	defusedcyber.com	/cucm-cve-2026-20230-fullchain-sweep	2026-06-24
Reported exploitation	cisa.gov	/sites/default/files/feeds/known_exploited_vulnerabilities.json	2026-06-25
Reported exploitation	sec.cloudapps.cisco.com	/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-ssrf-cXPnHcW	2026-07-01
Reported exploitation	recordedfuture.com	/blog/june-2026-cve-landscape	2026-07-10
Exploit reference	VulnCheck XDB 0bab51e2df38	Exploit type: initial-access	2026-06-25

Evidence

Source

Detail

Date

Honeypot sighting

Shadowserver honeypots

Exploitation attempts seen on 1 day

2026-07-10

Reported exploitation

x.com

/defusedcyber/status/2069074520057557244

2026-06-22

Reported exploitation

defusedcyber.com

/cucm-cve-2026-20230-fullchain-sweep

2026-06-24

Reported exploitation

cisa.gov

/sites/default/files/feeds/known_exploited_vulnerabilities.json

2026-06-25

Reported exploitation

sec.cloudapps.cisco.com

/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-ssrf-cXPnHcW

2026-07-01

Reported exploitation

recordedfuture.com

/blog/june-2026-cve-landscape

2026-07-10

Exploit reference

VulnCheck XDB 0bab51e2df38

Exploit type: initial-access

2026-06-25

3 of these are GitHub repositories with fewer than 5 stars. They are listed for reference and don't count toward the exploitation status above.

Index	Artifact	Stars	First seen
GitHub PoC	W5M1n9/Cisco-Unified-Communications-Manager-Server-Side-Forgery-Request-Vulnerability-CVE-2026-20230	1	2026-06-25
GitHub PoC	CVE-2026-20230 - Cisco Unified CM	1	2026-06-05
GitHub PoC	Cisco Unified Communications Manager (Unified CM) deployments affected by CVE-2026-20230.		2026-06-12

Waratek protection

Outside Waratek scope

A Java vulnerability, but not one Waratek protects. It affects only Java on a user's desktop (applets, Web Start, JavaFX, the installer), sits in a product the Waratek agent can't be installed into, or is in a package we don't expect in business applications. The decision below says which.

Protection none
Action not pursued none
Review automated Upstream data
Record active

Decided by	The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached
Finding	This CVE names only products the Waratek agent cannot be installed into (cisco/unified_communications_manager). They ship as sealed appliance images or as native code with no application JVM, so there is no start-up line to add -javaagent to. The vulnerability may well be a Java one; it is permanently out of ARMR's reach rather than outside its subject.

Decided by

The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached

Finding

This CVE names only products the Waratek agent cannot be installed into (cisco/unified_communications_manager). They ship as sealed appliance images or as native code with no application JVM, so there is no start-up line to add -javaagent to. The vulnerability may well be a Java one; it is permanently out of ARMR's reach rather than outside its subject.

Affected software and releases

Products and versions

1 product, 2 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	cisco	unified communications manager	generic	≥ 14.0 and ＜ 14.6 · ≥ 15.0 and ≤ 15.4

Source

Vendor

Product

Scheme

Affected versions

nvd

cisco

unified communications manager

generic

≥ 14.0 and ＜ 14.6 · ≥ 15.0 and ≤ 15.4

References

URL	Tags
https://www.cisco.com/c/en/us/support/docs/csa/cisco-sa-cucm-ssrf-cXPnHcW.html
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-ssrf-cXPnHcW	Vendor Advisory
https://denizhalil.com/2026/06/12/cve-2026-20230-cisco-unified-cm-ssrf/	Exploit, Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20230	US Government Resource

URL

Timeline

Published	2026-06-03	By the CVE Program.
VulnCheck KEV: earliest evidence	2026-06-22	Date of the oldest evidence of exploitation in VulnCheck KEV's record. VulnCheck does not publish the date it listed the CVE.
Added to CISA KEV	2026-06-25	Listed in CISA's Known Exploited Vulnerabilities catalog.
VulnCheck KEV: latest evidence	2026-07-10	Date of the newest report, exploit reference or honeypot sighting in VulnCheck KEV's record.
NVD record modified	2026-10-07	NVD's own last-modified date for this record.

Published

2026-06-03

By the CVE Program.

VulnCheck KEV: earliest evidence

2026-06-22

Date of the oldest evidence of exploitation in VulnCheck KEV's record. VulnCheck does not publish the date it listed the CVE.

Added to CISA KEV

2026-06-25

Listed in CISA's Known Exploited Vulnerabilities catalog.

VulnCheck KEV: latest evidence

2026-07-10

Date of the newest report, exploit reference or honeypot sighting in VulnCheck KEV's record.

NVD record modified

2026-10-07

NVD's own last-modified date for this record.

How VRT decided (15 of 24 rules ran)

15 of 24 rules ran. The rest didn't run because an earlier rule had already settled the CVE.

# Rule Outcome Status Detail

identity: Does this identifier describe a vulnerability at all? the first rule that matches decides

1 rejected no match CVE Program withdrawal of this identifier

scope: Is it a vulnerability Waratek protects? the first rule that matches decides

2 armr-patch-file no match An ARMR patch file on disk for this CVE

3 armr-secure-rule-file no match An ARMR security-rule template on disk for this CVE

4 manual-classification no match A researcher's recorded decision for this specific CVE

5 manual classification no match Manual classification of this CVE in the legacy dataset

6 non-java-upstream no match A root cause in non-Java code: an OS kernel, a C library, or a bundled runtime

7 oracle-component no match The defect being in a component of a tracked product the agent does not reach: JavaFX, the Java SE installer, the JInitiator browser plug-in, the native WebLogic proxy plug-in, or a native part of Oracle Application Server or Collaboration Suite (HTTP Server, Web Cache, Internet Directory, mail and calendar servers). Oracle gives these no CPE of their own and names them only in the description.

8 java-client-side no match Oracle's own risk-matrix note saying the CVE is reached only through untrusted code in the Java sandbox (applets, Web Start) or only through a client installation of Java, so a server running its own trusted code is not exposed

9 osv-maven no match An OSV.dev record of this CVE affecting a package published to Maven Central. When every such package is one business applications do not use (Minecraft mods and launchers, Fastjson) and no tracked product is named by CPE, it settles the CVE as Outside Waratek scope instead

10 cna-maven-package no match An affected Maven artifact named by the CNA itself

11 known-cpe-product no match An NVD CPE naming a product ARMR tracks

12 cna-cpe-product no match A CPE the CNA published naming a tracked product. Oracle publishes these on advisory day, months before NVD.

13 oracle-advisory-family no match A tracked product family named in Oracle's own risk matrix. CPE cannot carry a suite name, only a module.

14 cna-named-product no match A tracked product named in words by the CVE's own CNA, on a record with no CPE yet. Apache and Eclipse publish these on advisory day, before NVD adds CPE data.

15 non-deployable-product decided it matched Outside Waratek scope Named products cannot host a Java agent: cisco/unified_communications_manager

16 unmatched-product not reached No tracked product matched above, and none present at all

disposition: What do we do about one that is? every rule runs

17 patch-hint not reached A reference pointing at the upstream fix: a commit, a PR, a Red Hat bug

18 open-source-maven not reached The affected package being open source on Maven, so the fix can be read

19 poc-derivable not reached An indexed exploit clearing the evidence bar to reverse-engineer, where there is no source to read

20 no-exploit not reached Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read

21 secure-rule-match not reached A vulnerability class already blocked by an ARMR security rule

22 exploited-no-fix-or-poc not reached Somebody exploiting this CVE (a CISA or VulnCheck KEV listing, or a CISA verdict of active exploitation), with no fix, source code or PoC to build a rule from

23 below-action-threshold not reached Medium or Low severity, no CISA or VulnCheck KEV listing, no PoC clearing the evidence bar, no CISA verdict, no Oracle advisory

24 no-exploit-published not reached Exploit code for this candidate, published in a reviewed catalogue or a GitHub repository with 5 or more stars, or in use per CISA or VulnCheck; not only a CISA verdict, a forecast, or nothing at all

Products the scope rules checked

The products this CVE's record names, and whether VRT tracks each one. The scope rules decided on these.

Vendor Product Tracked CPE Source

cisco unified_communications_manager not tracked cpe:2.3:a:cisco:unified_communications_manager:*:*:*:*:-:*:*:*

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