How severe is CVE-2018-19204?

CVE-2018-19204 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-19204 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-19204?

CVE-2018-19204 affects Paessler Prtg Network Monitor. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-19204?

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

When was CVE-2018-19204 published?

CVE-2018-19204 was published on 2018-11-12 and last updated on 2026-06-17.

CVE-2018-19204

CVE-2018-19204 is a high-severity vulnerability in Paessler Prtg Network Monitor with a CVSS 3.x base score of 8.8. 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Paessler Prtg Network Monitor
Published: 2018-11-12
Last modified: 2026-06-17

Description

PRTG Network Monitor before 18.3.44.2054 allows a remote authenticated attacker (with read-write privileges) to execute arbitrary code and OS commands with system privileges. When creating an HTTP Advanced Sensor, the user's input in the POST parameter 'proxyport_' is mishandled. The attacker can craft an HTTP request and override the 'writeresult' command-line parameter for HttpAdvancedSensor.exe to store arbitrary data in an arbitrary place on the file system. For example, the attacker can create an executable file in the \Custom Sensors\EXE directory and execute it by creating EXE/Script Sensor.

Frequently asked questions

What is CVE-2018-19204?: PRTG Network Monitor before 18.3.44.2054 allows a remote authenticated attacker (with read-write privileges) to execute arbitrary code and OS commands with system privileges. When creating an HTTP Advanced Sensor, the user's input in the POST parameter 'proxyport_' is mishandled. The attacker can craft an HTTP request and override the 'writeresult' command-line parameter for HttpAdvancedSensor.exe to store arbitrary data in an arbitrary place on the file system. For example, the attacker can create an executable file in the \Custom Sensors\EXE directory and execute it by creating EXE/Script Sensor.
How severe is CVE-2018-19204?: CVE-2018-19204 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-19204 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-19204?: CVE-2018-19204 affects Paessler Prtg Network Monitor. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-19204?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-19204 published?: CVE-2018-19204 was published on 2018-11-12 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:paessler:prtg_network_monitor:*:*:*:*:*:*:*:*

More vulnerabilities in Paessler Prtg Network Monitor

CVE-2020-10374 — Critical (CVSS 9.8): A webserver component in Paessler PRTG Network Monitor 19.2.50 to PRTG 20.1.56 allows unauthenticated remote command…
CVE-2018-19410 — Critical (CVSS 9.8): PRTG Network Monitor before 18.2.40.1683 allows remote unauthenticated attackers to create users with read-write…
CVE-2023-31452 — High (CVSS 8.8): A cross-site request forgery (CSRF) token bypass was identified in PRTG 23.2.84.1566 and earlier versions that allows…
CVE-2018-19411 — High (CVSS 8.8): PRTG Network Monitor before 18.2.40.1683 allows an authenticated user with a read-only account to create another user…
CVE-2018-19203 — High (CVSS 7.5): PRTG Network Monitor before 18.2.41.1652 allows remote unauthenticated attackers to terminate the PRTG Core Server…
CVE-2018-10253 — High (CVSS 7.5): Paessler PRTG Network Monitor before 18.1.39.1648 mishandles stack memory during unspecified API calls.

All CVEs affecting Paessler Prtg Network Monitor →

Other CWE-20 (Improper Input Validation) vulnerabilities

CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48277 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48055 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download any video media. In versions 2.4.0 and…
CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
CVE-2026-33587 — Critical (CVSS 10.0): Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and…

Browse all CWE-20 (Improper Input Validation) vulnerabilities →