PatchSiren cyber security CVE debrief
CVE-2026-56785 FlatPress CVE debrief
CVE-2026-56785 is a stored cross-site scripting vulnerability in FlatPress, a content management system. The vulnerability exists in the comment and contact forms, where the name, URL, and email fields are rendered without proper output encoding in Smarty templates. This allows attackers to inject arbitrary HTML and JavaScript, which can be executed in the browsers of viewers, including administrators. The vulnerability has a CVSS score of 8.4 and is classified as HIGH severity. The CVE was published on 2026-06-23T23:16:50.020Z and last modified on 2026-06-25T19:25:34.880Z.
- Vendor
- FlatPress
- Product
- Unknown
- CVSS
- HIGH 8.4
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-06-23
- Original CVE updated
- 2026-06-25
- Advisory published
- 2026-06-23
- Advisory updated
- 2026-06-25
Who should care
Administrators and users of FlatPress should be aware of this vulnerability, as it can allow attackers to inject malicious scripts and potentially take control of user sessions or steal sensitive information. Users who have not updated to the latest version of FlatPress should take immediate action to patch the vulnerability. Additionally, users who have not properly configured their Smarty templates may be more vulnerable to this exploit.
Technical summary
The vulnerability exists in the comment and contact forms of FlatPress, where the name, URL, and email fields are not properly encoded. This allows attackers to inject arbitrary HTML and JavaScript, which can be executed in the browsers of viewers. The vulnerability is caused by the lack of output encoding in Smarty templates. The CVSS vector for this vulnerability is CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:H/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X.
Defensive priority
High priority should be given to patching this vulnerability, as it can allow attackers to inject malicious scripts and potentially take control of user sessions or steal sensitive information. Administrators should update to the latest version of FlatPress and ensure that Smarty templates are properly configured to prevent this exploit.
Recommended defensive actions
- Update to the latest version of FlatPress
- Ensure Smarty templates are properly configured to prevent injection of malicious scripts
- Monitor for suspicious activity on the website
- Implement additional security measures, such as web application firewalls and intrusion detection systems
- Educate users on the risks of this vulnerability and the importance of patching
Evidence notes
The CVE-2026-56785 vulnerability was reported by Vulncheck and is classified as a stored cross-site scripting vulnerability. The vulnerability exists in the comment and contact forms of FlatPress, where the name, URL, and email fields are not properly encoded. The CVSS score for this vulnerability is 8.4, and it is classified as HIGH severity. The CVE was published on 2026-06-23T23:16:50.020Z and last modified on 2026-06-25T19:25:34.880Z.
Sources and references
Verified primary and authoritative sources
-
CVE-2026-56785 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-56785
CVE Program - Official CVE Program record with source-provided CVE metadata.
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CVE-2026-56785 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-56785
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Supplemental references
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Source reference
Unverified legacy reference
URL: https://github.com/dilipk5/flatpressd-cms-sxss
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Source reference
Unverified legacy reference
URL: https://github.com/flatpressblog/flatpress/commit/10be83cbaac5ce0e51250b9d57de7f257b8f34f8
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Source reference
Unverified legacy reference
URL: https://www.vulncheck.com/advisories/flatpress-stored-cross-site-scripting-via-unescaped-comment-and-contact-form-fields
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.