CVE-2019-16517

Name: CVE-2019-16517
Creator: NVD / NIST
Published: 2020-01-23T18:15:13.803+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 1.33%

Last modified Jun 17, 2026

CVE-2019-16517 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. An issue was discovered in ConnectWise Control (formerly known as ScreenConnect) 19.3.25270.7185. There is a CORS misconfiguration, which reflected the Origin provided by incoming requests. EPSS estimates a 1.33% chance of exploitation in the next 30 days.

Description

An issue was discovered in ConnectWise Control (formerly known as ScreenConnect) 19.3.25270.7185. There is a CORS misconfiguration, which reflected the Origin provided by incoming requests. This allowed JavaScript running on any domain to interact with the server APIs and perform administrative actions, without the victim's knowledge.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

1.33%

67.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-346

Affected Software

Vendor	Product	Versions
Connectwise	Control	19.3.25270.7185

References

https://blog.huntresslabs.com/validating-the-bishop-fox-findings-in-connectwise-control-9155eec36a34Exploit, Third Party Advisory
https://know.bishopfox.com/advisoriesThird Party Advisory
https://know.bishopfox.com/advisories/connectwise-controlExploit, Third Party Advisory
https://www.crn.com/news/managed-services/connectwise-control-msp-security-vulnerabilities-are-severe-bishop-foxThird Party Advisory
https://www.crn.com/slide-shows/managed-services/connectwise-control-attack-chain-exploit-20-questions-for-security-researcher-bishop-foxThird Party Advisory
https://blog.huntresslabs.com/validating-the-bishop-fox-findings-in-connectwise-control-9155eec36a34Exploit, Third Party Advisory
https://know.bishopfox.com/advisoriesThird Party Advisory
https://know.bishopfox.com/advisories/connectwise-controlExploit, Third Party Advisory
https://www.crn.com/news/managed-services/connectwise-control-msp-security-vulnerabilities-are-severe-bishop-foxThird Party Advisory
https://www.crn.com/slide-shows/managed-services/connectwise-control-attack-chain-exploit-20-questions-for-security-researcher-bishop-foxThird Party Advisory

Timeline

Published: Jan 23, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-16517?

How severe is CVE-2019-16517?

CVE-2019-16517 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 1.33% probability of exploitation in the next 30 days.

How do I fix CVE-2019-16517?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2019-16517?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST