CVE-2026-49841
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk32th percentile - higher than 32% of all known CVEs
Summary
FreeSWITCH prior to version 1.11.1 has a heap overflow vulnerability in the mod_verto module. An attacker can send an HTTP POST request with a large body, causing a buffer overflow before authentication.
Risk Assessment
An attacker can remotely take control of the FreeSWITCH server without authentication, potentially compromising communication confidentiality and integrity.
Recommendation
Immediately upgrade FreeSWITCH to version 1.11.1 or later.
Original NVD description (English source)
FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to version 1.11.1, the mod_verto HTTP request handler allocates a fixed 2 MiB buffer for a POST application/x-www-form-urlencoded body but accepts Content-Length up to just under 10 MiB. The body-read loop is bounded by Content-Length rather than the buffer size, producing an attacker-controlled heap overflow of up to ~8 MiB -- before the HTTP basic-auth check runs. This issue has been patched in version 1.11.1.