Vulnerability · Published Jun 9, 2026 · Assigned by GitHub_M

CVE-2026-49843FreeSWITCH: Pre-authentication session eviction via attacker-chosen `sessid` in `mod_verto`

Medium 5.3

In plain English

A medium-severity improper authentication 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 0.3% (higher than 21% of all known vulnerabilities).

Severity (CVSS 3.1)5.3Medium

Exploit odds (30 days)0.3%top 79.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

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 JSON-RPC handler bound the connection to the client-supplied sessid on the first frame, before the authentication gate. Binding inserts the connection into the global session hash and, on a key collision, drops the prior occupant of that slot — sending it a verto.punt, detaching its calls, and closing its socket. An unauthenticated network attacker who knows a target session UUID could therefore evict the legitimate client. This issue has been patched in version 1.11.1.

Affected products (as reported)

Vendor	Product	Versions
signalwire	freeswitch	< 1.11.1

Weakness: CWE-287 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References

https://github.com/signalwire/freeswitch/security/advisories/GHSA-9457-fxr9-x78m x_refsource_CONFIRM
https://github.com/signalwire/freeswitch/releases/tag/v1.11.1 x_refsource_MISC