CVE-2023-51803

CRITICAL
Published Apr 1, 2024 Modified Apr 15, 2026 CWE-674

Description

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

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CVSS v3.1 Score

9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-674 CWE-674

References

Frequently Asked Questions

What is CVE-2023-51803? +
LinuxServer.io Heimdall before 2.5.7 does not prevent use of icons that have non-image data such as the "<?php ?>" substring. It has a CVSS v3.1 base score of 9.8 (CRITICAL).
How severe is CVE-2023-51803? +
CVE-2023-51803 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.
How do I check if I'm vulnerable to CVE-2023-51803? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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