CVE-2015-4226: The packet-storing feature on Cisco 9900 phones with firmware 9.3(2) does not properly support the RTP prot...

Security readout for executives and security teams

This issue can make affected Cisco 9900 Series IP phones hang during a call. The public record says malformed RTP traffic after a call is answered can trigger denial of service. It is primarily an availability risk for voice communications, not a data-theft issue based on the provided sources. Exposure is limited to organizations still running Cisco 9900 Series phones on firmware 9.3(2), especially where RTP traffic can reach phones after call setup. The bundle does not identify other models, versions, or products as affected. Treat as a targeted voice-availability issue. Prioritize if the business depends on Cisco 9900 phones for critical operations, call centers, emergency response, or executive communications. Otherwise, handle through normal lifecycle and firmware management. Mitigation focus: Inventory Cisco 9900 phones and identify firmware 9.3(2).; Check Cisco advisory for fixed firmware or supported remediation guidance.; Plan vendor-supported firmware remediation if Cisco identifies an upgrade path..

Prepared

Jun 13, 2026, 22:22 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.