CVE-2026-71236

HIGH
Published Aug 5, 2026 Modified Aug 5, 2026 CWE-79

Description

Grocy's API request-body parser (controllers/Api/BaseApiController.php, GetParsedAndFilteredRequestBody) purifies incoming field values with HTMLPurifier, then manually reverses HTML-entity encoding of the resulting output by replacing &amp;lt;, &amp;gt;, and &amp;amp; back to <, >, and & immediately after purification. This double-decode reconstructs live HTML/script tags from the entity-encoded form that HTMLPurifier produced to neutralize them, re-introducing stored XSS across API-writable fields (products, recipes, stock, users, chores, and others) that are rendered elsewhere without re-sanitization.

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CVSS v3.1 Score

8.7
HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

References

Frequently Asked Questions

What is CVE-2026-71236? +
Grocy's API request-body parser (controllers/Api/BaseApiController.php, GetParsedAndFilteredRequestBody) purifies incoming field values with HTMLPurifier, then manually reverses HTML-entity encoding of the resulting output by replacing &amp;lt;, &amp;gt;, and &amp;amp; back to <, >, and & immediately after purification. This double-decode reconstructs live HTML/script tags from the entity-encoded form that HTMLPurifier produced to neutralize them, re-introducing stored XSS across API-writable fields (products, recipes, stock, users, chores, and others) that are rendered elsewhere without re-sanitization. It has a CVSS v3.1 base score of 8.7 (HIGH).
How severe is CVE-2026-71236? +
CVE-2026-71236 has a CVSS v3.1 score of 8.7 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.
How do I check if I'm vulnerable to CVE-2026-71236? +
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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