CVE-2026-52747
highpriority · track · 34EPSS 0.005 · 41 %ileDEEUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (6)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-2138OWASP ModSecurity: Mehrere Schwachstellen ermöglichen Umgehen von SicherheitsvorkehrungenDeutsch2026-06-29csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in OWASP ModSecurity ausnutzen, um Sicherheitsvorkehrungen zu umgehen.
- BIT-modsecurity-2026-52747ModSecurity: Multipart form-data parser silently strips embedded line breaks from form-field values, enabling request-body inspection bypass2026-07-15vendor · osvUS
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.
- BIT-modsecurity2-2026-52747ModSecurity: Multipart form-data parser silently strips embedded line breaks from form-field values, enabling request-body inspection bypass2026-07-15vendor · osvUS
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.
also known as (4)
Other names and identifiers for this entity.
- CNNVD-2026-47014448cnnvd
- EUVD-2026-43047enisa_euvd
- BIT-modsecurity-2026-52747osv
- GHSA-rcw9-2f5r-7p88osv
sources
Which sources assert this record, and when.
references (10)
External citations — patches, advisories, analysis.
- https://github.com/owasp-modsecurity/ModSecurity/commit/875504c2758169c41be1ad2f0cc64d896b7815d7cnnvd
- https://github.com/owasp-modsecurity/ModSecurity/releasesPatchcnnvd
- https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.16cnnvd
- https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-rcw9-2f5r-7p88cnnvd
- https://github.com/owasp-modsecurity/ModSecurity/commit/875504c2758169c41be1ad2f0cc64d896b7815d7enisa_euvd
- https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.16enisa_euvd
- https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-rcw9-2f5r-7p88enisa_euvd
- https://github.com/owasp-modsecurity/ModSecurity/commit/875504c2758169c41be1ad2f0cc64d896b7815d7Patchnvd
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