Vulnerability · Published Jun 9, 2026 · Assigned by GitHub_M
CVE-2026-49842FreeSWITCH: Pre-authentication bandwidth amplification via `mod_verto` speed-test frames
High 7.5
In plain English
A high-severity uncontrolled resource consumption in freeswitch from signalwire. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 39% of all known vulnerabilities).
Official 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 version 1.11.1, mod_verto's WebSocket frame loop intercepts a #-prefixed speed-test protocol (#SPU / #SPB / #SPE) before any authentication check. The declared payload size in #SPU was parsed with atoi() and only rejected non-positive values, so an unauthenticated peer could request up to INT_MAX bytes. The server then wrote roughly size * 10 bytes back during the download phase, on the order of 20 GB per request, yielding strong outbound bandwidth amplification from a short request. This issue has been patched in version 1.11.1.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| signalwire | freeswitch | < 1.11.1 |
Weakness: CWE-400 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/signalwire/freeswitch/security/advisories/GHSA-p3gx-p2w7-wp35 x_refsource_CONFIRM
- https://github.com/signalwire/freeswitch/releases/tag/v1.11.1 x_refsource_MISC