# CVE-2026-104269

ModSecurity filename parsing mismatch allows WAF bypass and malicious file uploads

- Page: https://www.vulneraibility.com/cve/CVE-2026-104269
- CVSS: 8.6
- Known exploited: not in CISA KEV as of our last sync
- EPSS: 0.57% (percentile 47.3)
- Weakness: CWE-436
- Also known as: GHSA-5pww-8rfg-9crf
- Published: 2026-11-05

## Affected versions

- owasp-modsecurity ModSecurity: affected >= 3.0.0 and < 3.0.17

A version outside these ranges is not a statement that it is unaffected.

## Impact

Content-Disposition filename/filename* mismatch lets attackers bypass WAF MULTIPART_FILENAME checks, enabling uninspected malicious file uploads and possible RCE or data compromise.

## Action

Immediate action required

## Recommendation

Upgrade to ModSecurity v3.0.17; validate backend filename/content-type checks; review upload logs.

## References

- [other] https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-5pww-8rfg-9crf
- [other] https://github.com/owasp-modsecurity/ModSecurity/commit/463db0c840fa27bfba095b0406a63004a12884b0
- [other] https://github.com/owasp-modsecurity/ModSecurity/commit/c6bd53d2dd96766b3afdc35d9929ebb20925d13d
- [other] https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v2.9.15
- [other] https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.17

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.