CVE-2021-37624

Public Exploit
FreeSWITCH does not authenticate SIP MESSAGE requests, leading to spam and message spoofing

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 1.10.7, FreeSWITCH does not authenticate SIP MESSAGE requests, leading to spam and message spoofing. By default, SIP requests of the type MESSAGE (RFC 3428) are not authenticated in the affected versions of FreeSWITCH. MESSAGE requests are relayed to SIP user agents registered with the FreeSWITCH server without requiring any authentication. Although this behaviour can be changed by setting the `auth-messages` parameter to `true`, it is not the default setting. Abuse of this security issue allows attackers to send SIP MESSAGE messages to any SIP user agent that is registered with the server without requiring authentication. Additionally, since no authentication is required, chat messages can be spoofed to appear to come from trusted entities. Therefore, abuse can lead to spam and enable social engineering, phishing and similar attacks. This issue is patched in version 1.10.7. Maintainers recommend that this SIP message type is authenticated by default so that FreeSWITCH administrators do not need to be explicitly set the `auth-messages` parameter. When following such a recommendation, a new parameter can be introduced to explicitly disable authentication.

Categories

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.55% Top 20%
Third-Party Advisory packetstormsecurity.com Third-Party Advisory seclists.org Third-Party Advisory openwall.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: signalwire freeswitch
Published at:
Updated at:

References

Link Tags
https://github.com/signalwire/freeswitch/security/advisories/GHSA-mjcm-q9h8-9xv3 third party advisory
https://github.com/signalwire/freeswitch/releases/tag/v1.10.7 third party advisory
http://www.openwall.com/lists/oss-security/2021/10/25/6 third party advisory mailing list
http://packetstormsecurity.com/files/164628/FreeSWITCH-1.10.6-Missing-SIP-MESSAGE-Authentication.html exploit vdb entry third party advisory
http://seclists.org/fulldisclosure/2021/Oct/44 mailing list exploit third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-37624?
CVE-2021-37624 has been scored as a high severity vulnerability.
How to fix CVE-2021-37624?
To fix CVE-2021-37624, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-37624 being actively exploited in the wild?
It is possible that CVE-2021-37624 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-37624?
CVE-2021-37624 affects signalwire freeswitch.
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