What’s Vulnerable › Vulnerabilities

CVE-2020-17451

• Severity: medium (CVSS 4.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2020-08-09 · updated 2026-06-17
• Weakness: CWE-79

Description

flatCore before 1.5.7 allows XSS by an admin via the acp/acp.php?tn=pages&sub=edit&editpage=1 page_linkname, page_title, page_content, or page_extracontent parameter, or the acp/acp.php?tn=system&sub=sys_pref prefs_pagename, prefs_pagetitle, or prefs_pagesubtitle parameter.

Affected products

• Flatcore: before 1.5.7 — fixed in 1.5.7

How to fix

Upgrade to a fixed version: Flatcore 1.5.7. Check the vendor advisory for mitigations.

References

• https://lists.openwall.net/full-disclosure/2020/08/07/1
• https://sec-consult.com/en/blog/advisories/multiple-vulnerabilities-in-flatcore-cms/
• https://lists.openwall.net/full-disclosure/2020/08/07/1
• https://sec-consult.com/en/blog/advisories/multiple-vulnerabilities-in-flatcore-cms/

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