CVE-2021-21355

描述

TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 8.7.40, 9.5.25, 10.4.14, 11.1.1, due to the lack of ensuring file extensions belong to configured allowed mime-types, attackers can upload arbitrary data with arbitrary file extensions - however, default _fileDenyPattern_ successfully blocked files like _.htaccess_ or _malicious.php_. Besides that, _UploadedFileReferenceConverter_ transforming uploaded files into proper FileReference domain model objects handles possible file uploads for other extensions as well - given those extensions use the Extbase MVC framework, make use of FileReference items in their direct or inherited domain model definitions and did not implement their own type converter. In case this scenario applies, _UploadedFileReferenceConverter_ accepts any file mime-type and persists files in the default location. In any way, uploaded files are placed in the default location _/fileadmin/user_upload/_, in most scenarios keeping the submitted filename - which allows attackers to directly reference files, or even correctly guess filenames used by other individuals, disclosing this information. No authentication is required to exploit this vulnerability. This is fixed in versions 8.7.40, 9.5.25, 10.4.14, 11.1.1.

如何修補 CVE-2021-21355

要修補 CVE-2021-21355,請將受影響套件升級到下列已修補版本。

• —升級至 10.4.14 或更新版本
• —升級至 10.4.14 或更新版本
• —升級至 8.7.40 或更新版本

CVE-2021-21355 正在被利用嗎?

低 — EPSS 為 1.6%,目前沒有觀察到大規模利用活動。

受影響套件(3)

• >= 10.0.0, < 10.4.14