CVE-2026-15305: TYPO3 CMS - Unrestricted File Upload in Form Framework
Vulnerability summary
CVE-2026-15305 is a medium (CVSS 6.3) Insufficient Type Distinction vulnerability in typo3 typo3 cms. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 16.9% of scored vulnerabilities.
Not severe (CVSS 6.3, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Timeline
- 14-07-2026PublishedVulnerability first disclosed.
- 15-07-2026Last modifiedVulnerability information updated.
Description
Users were able to upload files with arbitrary MIME types to forms using FileUpload or ImageUpload elements with allowedMimeTypes configured. The restriction was not enforced server-side because the MimeTypeValidator was registered during form building before concrete form definition properties were applied, resulting in the validator never being added to the processing pipeline. This issue affects TYPO3 CMS versions 14.2.0-14.3.4.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST6.3MediumCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/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
EPSS trend
Probability
0.25%
Chance of exploitation in the next 30 days
Percentile
17%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.25% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Typo31 product
- typo3 cms≥ 14.2.0, < 14.3.5
1 vendor · 1 product
References
3 links- typo3.org/security/advisory/typo3-core-sa-2026-020Vendor Advisory