CVE-2026-49843

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

MEDIUM
5.3
CVSS Score
Published: June 9, 2026 at 04:04 PM UTC
Updated: July 23, 2026 at 07:32 PM UTC
2 products affected across 2 vendorsFreeswitchFreeswitch

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

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

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.11.1
Affected range stops below 1.11.1, so it looks safe — our inference, not a vendor statement
v < 1.11.1
Affected range stops below 1.11.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (2)

x_refsource_CONFIRMThird Party Advisory
Source: cverecord
https://github.com/signalwire/freeswitch/security/advisories/GHSA-9457-fxr9-x78m
x_refsource_MISCRelease Notes
Source: cverecord
https://github.com/signalwire/freeswitch/releases/tag/v1.11.1

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Vector?

Quick Info

StatusANALYZED
CWE
CWE-287

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