How severe is CVE-2019-16517?

CVE-2019-16517 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-16517 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-16517?

CVE-2019-16517 affects Connectwise Control. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-16517?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2019-16517 published?

CVE-2019-16517 was published on 2020-01-23 and last updated on 2026-06-17.

CVE-2019-16517

CVE-2019-16517 is a critical-severity vulnerability in Connectwise Control with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-346.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-346
Affected product: Connectwise Control
Published: 2020-01-23
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2019-16517?: 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.
How severe is CVE-2019-16517?: CVE-2019-16517 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-16517 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-16517?: CVE-2019-16517 affects Connectwise Control. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-16517?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2019-16517 published?: CVE-2019-16517 was published on 2020-01-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:connectwise:control:19.3.25270.7185:*:*:*:*:*:*:*

More vulnerabilities in Connectwise Control

CVE-2023-25718 — Critical (CVSS 9.8): In ConnectWise Control through 22.9.10032 (formerly known as ScreenConnect), after an executable file is signed,…
CVE-2023-25719 — High (CVSS 8.8): ConnectWise Control before 22.9.10032 (formerly known as ScreenConnect) fails to validate user-supplied parameters such…
CVE-2019-16513 — High (CVSS 8.8): An issue was discovered in ConnectWise Control (formerly known as ScreenConnect) 19.3.25270.7185. CSRF can be used to…
CVE-2019-16514 — High (CVSS 7.2): An issue was discovered in ConnectWise Control (formerly known as ScreenConnect) 19.3.25270.7185. The server allows…
CVE-2019-16515 — Medium (CVSS 6.5): An issue was discovered in ConnectWise Control (formerly known as ScreenConnect) 19.3.25270.7185. Certain HTTP security…
CVE-2019-16516 — Medium (CVSS 5.3): An issue was discovered in ConnectWise Control (formerly known as ScreenConnect) 19.3.25270.7185. There is a user…

All CVEs affecting Connectwise Control →

Other CWE-346 vulnerabilities

CVE-2026-42901 — Critical (CVSS 10.0): Origin validation error in Microsoft Entra ID allows an unauthorized attacker to elevate privileges over a network.
CVE-2026-6508 — Critical (CVSS 9.8): Origin Validation Error vulnerability in TUBITAK BILGEM Software Technologies Research Institute Liderahenk allows…
CVE-2026-2790 — Critical (CVSS 9.8): Same-origin policy bypass in the Networking: JAR component. This vulnerability was fixed in Firefox 148, Firefox ESR…
CVE-2022-50925 — Critical (CVSS 9.8): Prowise Reflect version 1.0.9 contains a remote keystroke injection vulnerability that allows attackers to send…
CVE-2025-30466 — Critical (CVSS 9.8): This issue was addressed through improved state management. This issue is fixed in Safari 18.4, iOS 18.4 and iPadOS…
CVE-2024-8487 — Critical (CVSS 9.8): A Cross-Origin Resource Sharing (CORS) vulnerability exists in modelscope/agentscope version v0.0.4. The CORS…

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