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CVE-2024-1709: ConnectWise ScreenConnect Authentication Bypass Vulnerability

CVE-2024-1709 is rated critical with a CVSS v3.1 base score of 10.0 and affects ConnectWise ScreenConnect. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available. CISA added it to its Known Exploited Vulnerabilities catalog on 2024-02-22, which means exploitation in the wild has been observed.

Vulnerability description

ConnectWise ScreenConnect 23.9.7 and prior are affected by an Authentication Bypass Using an Alternate Path or Channel vulnerability, which may allow an attacker direct access to confidential information or critical systems.

Severity breakdown

CVSS v3.1 10.0: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

• Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
• Attack complexity: Low. No special conditions; the attack can be repeated reliably.
• Privileges required: None. No account or prior access is needed.
• User interaction: None. No action from any user is needed.
• Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
• Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
• Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
• Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-288: Authentication Bypass Using an Alternate Path or Channel

The product requires authentication, but the product has an alternate path or channel that does not require authentication.

Affected products

• Connectwise Screenconnect: before 23.9.8

References

• https://github.com/rapid7/metasploit-framework/pull/18870
• https://www.connectwise.com/company/trust/security-bulletins/connectwise-screenconnect-23.9.8
• https://github.com/watchtowrlabs/connectwise-screenconnect_auth-bypass-add-user-poc
• https://techcrunch.com/2024/02/21/researchers-warn-high-risk-connectwise-flaw-under-attack-is-embarrassingly-easy-to-exploit/
• https://www.bleepingcomputer.com/news/security/connectwise-urges-screenconnect-admins-to-patch-critical-rce-flaw/
• https://www.horizon3.ai/attack-research/red-team/connectwise-screenconnect-auth-bypass-deep-dive/
• https://www.huntress.com/blog/a-catastrophe-for-control-understanding-the-screenconnect-authentication-bypass
• https://www.huntress.com/blog/detection-guidance-for-connectwise-cwe-288-2
• https://www.huntress.com/blog/vulnerability-reproduced-immediately-patch-screenconnect-23-9-8
• https://www.securityweek.com/connectwise-confirms-screenconnect-flaw-under-active-exploitation/
• https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-1709