{"id":"CVE-2026-20230","published":"2026-06-03T18:16:20Z","modified":"2026-10-07T19:17:37Z","title":"Cisco Unified Communications Manager Server-Side Request Forgery (SSRF) Vulnerability","vendor":"Cisco","product":"Unified Communications Manager","tier":"core","eol":null,"description":{"text":"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.\r\n\r\nThis 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.\r\nNote: 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.\r\nNote: To exploit this vulnerability, the WebDialer service must be enabled. WebDialer is disabled by default.","provenance":"source","from":"NVD"},"summary":{"text":"A flaw in the Cisco Unified Communications Manager and Unified Communications Manager Session Management Edition products stems from improper input validation of specific HTTP requests, enabling server-side request forgery. An unauthenticated remote attacker who sends a crafted HTTP request to an affected device can write files to the underlying operating system, which could later be used to elevate to root, but exploitation requires the WebDialer service to be enabled, which is disabled by default.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-29T13:44:08Z"},"cvss":{"score":8.6,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N","provenance":"source","from":"NVD"},"epss":{"score":0.88528,"percentile":0.99771,"date":"2026-10-30","provenance":"source"},"kev":{"dateAdded":"2026-06-25","dueDate":"2026-06-28","ransomware":false,"requiredAction":"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.","notes":"https://www.cisco.com/c/en/us/support/docs/csa/cisco-sa-cucm-ssrf-cXPnHcW.html ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-20230","provenance":"source"},"vulncheckKev":{"dateAdded":"2026-06-22","exploitedFirstSeen":"2026-06-22","ransomware":false,"evidence":[{"url":"https://x.com/defusedcyber/status/2069074520057557244","date":"2026-06-22"},{"url":"https://defusedcyber.com/cucm-cve-2026-20230-fullchain-sweep","date":"2026-06-24"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2026-06-25"},{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-ssrf-cXPnHcW","date":"2026-07-01"},{"url":"https://dashboard.shadowserver.org/statistics/honeypot/vulnerability/map/?day=2026-07-10&host_type=src&vulnerability=cve-2026-20230","date":"2026-07-10"},{"url":"https://www.recordedfuture.com/blog/june-2026-cve-landscape","date":"2026-07-10"}],"evidenceTotal":6,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 31, 2026","url":"https://otx.alienvault.com/pulse/6ae4aefab0c2191cecd41862","created":"2026-10-30"},{"name":"Actively_Exploited_Kev | Oct 30, 2026","url":"https://otx.alienvault.com/pulse/6ae35d889ea92b4ce19c2680","created":"2026-10-29"},{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"}],"provenance":"machine"},"cwes":[{"id":"CWE-918","name":"Server-Side Request Forgery"}],"references":[{"url":"https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cucm-ssrf-cXPnHcW","tags":["Vendor Advisory"]},{"url":"https://denizhalil.com/2026/06/12/cve-2026-20230-cisco-unified-cm-ssrf/","tags":["Exploit","Third Party Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20230","tags":["US Government Resource"]}],"techniques":[{"id":"T1190","name":"Exploit Public-Facing Application","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: unauthenticated remote exploit of public-facing service","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"could allow an unauthenticated, remote attacker to conduct server-side request forgery","start":154,"end":240}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1105","name":"Ingress Tool Transfer","tactics":["command-and-control"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: attacker writes files to the OS","mappingType":"primary_impact","evidence":[{"from":"description","quote":"could allow the attacker to write files to the underlying operating system","start":493,"end":567}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2026-34137","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-34137","exploited":true,"exploitedSince":"2026-06-25","provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":3,"skipped":0,"earliest":"2026-06-05","earliestUrl":"https://github.com/HORKimhab/CVE-2026-20230","repos":[{"name":"HORKimhab/CVE-2026-20230","url":"https://github.com/HORKimhab/CVE-2026-20230","stars":1,"created":"2026-06-05"},{"name":"W5M1n9/Cisco-Unified-Communications-Manager-Server-Side-Forgery-Request-Vulnerability-CVE-2026-20230","url":"https://github.com/W5M1n9/Cisco-Unified-Communications-Manager-Server-Side-Forgery-Request-Vulnerability-CVE-2026-20230","stars":1,"created":"2026-06-25"},{"name":"HalilDeniz/CVE-2026-20230-Scanner","url":"https://github.com/HalilDeniz/CVE-2026-20230-Scanner","stars":0,"created":"2026-06-12"}]},"first":{"date":"2026-06-05","source":"PoC-in-GitHub","url":"https://github.com/HORKimhab/CVE-2026-20230"},"provenance":"source"},"exploitRefs":["https://denizhalil.com/2026/06/12/cve-2026-20230-cisco-unified-cm-ssrf/"],"flow":[{"stage":"exploitation","techniques":["T1190"],"provenance":"ai"},{"stage":"primary","techniques":["T1105"],"provenance":"ai"}],"timeline":[{"date":"2026-06-03","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-20230","provenance":"source"},{"date":"2026-06-05","kind":"exploit-public","label":"First public exploit: PoC-in-GitHub","url":"https://github.com/HORKimhab/CVE-2026-20230","provenance":"source"},{"date":"2026-06-22","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://x.com/defusedcyber/status/2069074520057557244","provenance":"source"},{"date":"2026-06-25","kind":"kev","label":"Added to CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2026-06-25","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-34137","provenance":"source"}],"speed":{"daysToPublicExploit":2,"firstExploitFrom":"PoC-in-GitHub","daysToKev":22},"priority":{"score":74.0,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":5.0,"detail":"added 131 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":19.95,"detail":"percentile 0.9977"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":5.0,"detail":"1 NVD reference tagged Exploit; 3 PoC-in-GitHub repos"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":6.02,"detail":"base score 8.6"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]}}