Vulnerabilities Cisco Warns of Available PoC for Critical Unified CM Vulnerability The high-severity flaw can be exploited remotely, without authentication, in server-side request forgery (SSRF) attacks. By Ionut Arghire | June 4, 2026 (4:44 AM ET) Flipboard Reddit Whatsapp Whatsapp Email Cisco on Wednesday rolled out patches for a high-severity vulnerability in Unified Communications Manager (Unified CM) and Unified Communications Manager Session Management Edition (Unified CM SME), warning that proof-of-concept (PoC) code for it exists. Tracked as CVE-2026-20230 (CVSS score of 8.6), the bug stems from input in specific HTTP requests not being properly validated, allowing attackers to mount server-side request forgery (SSRF) attacks. “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,” Cisco explains in its advisory . According to the company, the security defect should be considered critical because it could provide attackers with root privileges on the affected device. Cisco also notes that only appliances with the WebDialer service enabled are impacted. The service is disabled by default. The company released Unified CM and Unified CM SME version 14SU6, which resolves the security flaw. Cisco also plans to include the patches in Unified CM and Unified CM SME version 15SU5, which is expected to arrive in September. Advertisement. Scroll to continue reading. “The Cisco PSIRT is aware that proof-of-concept exploit code is available for the vulnerability described in this advisory,” the company says, adding that the CVE does not appear to have been exploited in attacks. On Wednesday, Cisco also rolled out fixes for two medium-severity vulnerabilities in Webex Meetings and Finesse, warning that unauthenticated, remote attackers could exploit them to conduct XSS attacks or load arbitrary files into active user sessions. Both issues are rooted in the insufficient validation of user input and can be exploited by convincing a user to click a malicious link, leading to the execution of arbitrary script code. Neither of the two security defects has been publicly disclosed or exploited in attacks, Cisco says. Additional information can be found on the company’s security advisories page. Related: Organizations Warned of Exploited Linux Kernel Vulnerability Related: Critical Vulnerability in HP VoIP Phones Enables Enterprise Network Breaches Related: Oracle’s First Monthly Patches Resolve 77 Vulnerabilities Related: Cisco Patches Critical Vulnerability in Secure Workload Written By Ionut Arghire Ionut Arghire is an international correspondent for SecurityWeek. 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Webinar: Third-Party Risk in Practice June 4, 2026 Organizations are investing heavily in third-party risk management, but breaches, delays, and blind spots continue to persist. Join this live webinar as we examine the gap between how organizations think their third-party risk programs are performing and what’s actually happening in practice. Register Virtual Roundtable: CISO Forum 2026 Mid-Year Review June 10, 2026 Explore how attackers are using AI to scale threats and how security teams can respond with AI-driven defenses. Protecting against unmonitored use of generative AI (Shadow AI) in business units and building and enforcing AI governance frameworks. Register People on the Move Rapid7 announced that Wael Mohamed will assume the role of Chief Executive Officer, replacing current Chief Executive Officer Corey Thomas, who will become Executive Chairman of the Board. Anurag Jain has been appointed Senior Vice President of Engineering at CodeHunter. CTERA has appointed Tal Sarfaty as Senior Vice President of Cybersecurity. More People On The Move Expert Insights The Zero-Knowledge Threat Actor and the End of Responsible Disclosure AI can help attackers generate malware, create malicious payloads, bypass simple security checks, and convert vague malicious intent into functional code. (Etay Maor) Raising the Cybersecurity Stakes: Ante up for the Agentic Era CISOs are now facing machine-speed attacks and asking, “How do I agent?” The industry must provide remediation at scale. (Nadir Izrael) Caught Off Guard: Securing AI After It Hits Production As enterprises rush AI projects into production, security teams are increasingly being forced into reactive mode. (Joshua Goldfarb) Cyber Resilience is the New Business Continuity Plan The organizations best prepared to face disruption are those that align security, continuity and risk management around what the business cannot afford to lose. (Steve Durbin) Enhancing Data Center Security Without Sacrificing Performance For AI data centers, where the stakes are the highest and performance constraints are the tightest, security and performance are no longer a zero-sum game. (Nadir Izrael) Flipboard Reddit Whatsapp Whatsapp Email