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CVE-2023-51803

LinuxServer.io Heimdall denial of service

9.8 CRITICALEPSS 0.70%
  1. Published31 Mar 2024

Description

LinuxServer.io Heimdall before 2.5.7 does not prevent use of icons that have non-image data such as the "<?php ?>" substring.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

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Frequently asked

Is CVE-2023-51803 being actively exploited?

CVE-2023-51803 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.70%.

How severe is CVE-2023-51803?

CVE-2023-51803 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 0.70% probability of exploitation.

How do I fix CVE-2023-51803?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2023-51803 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.