CVE-2021-41157

Public Exploit
FreeSWITCH does not authenticate SIP SUBSCRIBE requests by default

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. By default, SIP requests of the type SUBSCRIBE are not authenticated in the affected versions of FreeSWITCH. Abuse of this security issue allows attackers to subscribe to user agent event notifications without the need to authenticate. This abuse poses privacy concerns and might lead to social engineering or similar attacks. For example, attackers may be able to monitor the status of target SIP extensions. Although this issue was fixed in version v1.10.6, installations upgraded to the fixed version of FreeSWITCH from an older version, may still be vulnerable if the configuration is not updated accordingly. Software upgrades do not update the configuration by default. SIP SUBSCRIBE messages should be authenticated by default so that FreeSWITCH administrators do not need to explicitly set the `auth-subscriptions` parameter. When following such a recommendation, a new parameter can be introduced to explicitly disable authentication.

Categories

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.26%
Third-Party Advisory seclists.org Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: signalwire freeswitch
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-41157?
CVE-2021-41157 has been scored as a medium severity vulnerability.
How to fix CVE-2021-41157?
To fix CVE-2021-41157, 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-2021-41157 being actively exploited in the wild?
It is possible that CVE-2021-41157 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-41157?
CVE-2021-41157 affects signalwire freeswitch.
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