Vulnerability record · CVE-2026-116785 · published 5 November 2026
CVE-2026-116785: Freeswitch heap-based buffer overflow vulnerability
Freeswitch · Freeswitch
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 1.11.2, ws_read_frame() decoded a WebSocket frame's 64-bit extended payload length with a 32-bit byte swap and narrowed the result into a signed length. A value whose surviving low word became negative bypassed the signed size check and was reinterpreted as an enormous unsigned count, causing client bytes to overwrite memory beyond the 64 KiB receive buffer. Any client completing a /socket WebSocket upgrade on an enabled mod_xml_rpc endpoint reached the parser before HTTP authentication; both the module and WebSocket endpoint are disabled by default. The heap overwrite can corrupt connection pointers and crash FreeSWITCH, ending every concurrent session, although remote code execution has not been demonstrated. This issue is fixed in version 1.11.2.
Description
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 1.11.2, ws_read_frame() decoded a WebSocket frame's 64-bit extended payload length with a 32-bit byte swap and narrowed the result into a signed length. A value whose surviving low word became negative bypassed the signed size check and was reinterpreted as an enormous unsigned count, causing client bytes to overwrite memory beyond the 64 KiB receive buffer. Any client completing a /socket WebSocket upgrade on an enabled mod_xml_rpc endpoint reached the parser before HTTP authentication; both the module and WebSocket endpoint are disabled by default. The heap overwrite can corrupt connection pointers and crash FreeSWITCH, ending every concurrent session, although remote code execution has not been demonstrated. This issue is fixed in version 1.11.2.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
Track CVE-2026-116785 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-116785), CISA KEV, FIRST EPSS (scores of 2026-11-11). This page is refreshed as NVD updates the record.
