# CVE-2026-52747

## Summary

- **CVE ID:** CVE-2026-52747
- **Severity:** HIGH
- **CVSS Score:** 8.6 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N)
- **CWE:** CWE-180
- **Published:** Jul 10, 2026
- **Last Modified:** Jul 13, 2026

## Description

ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. Prior to 3.0.16, the multipart/form-data request body parser in libmodsecurity silently removes embedded line breaks from non-file form-field values before exporting them to ARGS and ARGS_POST because src/request_body_processor/multipart.cc overwrites reserved bytes in m_reserve instead of appending the current buffer. This creates a parser differential between ModSecurity and backend applications that preserve line breaks in form fields, allowing rules that inspect ARGS or ARGS_POST to miss payloads whose dangerous syntax depends on a line break. This issue is fixed in version 3.0.16.

## Affected Products

- owasp-modsecurity — ModSecurity (< 3.0.16)

## References

- [CNA](https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-rcw9-2f5r-7p88)
- [CNA](https://github.com/owasp-modsecurity/ModSecurity/commit/875504c2758169c41be1ad2f0cc64d896b7815d7)
- [CNA](https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.16)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.48%
- **EPSS Percentile:** 39.6

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-12._