CVE-2026-49842: high-severity vulnerability in signalwire freeswitch
FreeSWITCH: Pre-authentication bandwidth amplification via `mod_verto` speed-test frames
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.4%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
signalwire · freeswitchRelated CVEs — signalwire freeswitch
In the same product, most dangerous first.
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