Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-81891— elFinder: ZIP extraction bypasses uploadDeny MIME filter allowing PHP file upload (RCE)

Quick assessment

Affected
Studio-42 elFinder
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Studio 42 elFinder是Studio 42团队的一款基于Web的文件管理组件。 Studio 42 elFinder 2.1.70之前版本存在任意文件上传漏洞，该漏洞源于未将mimetypeInternalDetect()的结果通过mimeTypeNormalize()处理，导致具有ZIP上传权限的攻击者可将PHP可执行文件提取到web可访问目录，可能导致远程代码执行。

CVSS 8.1 · High EPSS 0.90% · P59

Affected Version Matrix 1

VendorProduct Version RangeStatus
Studio-42 elFinder < 2.1.70 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-81891

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
elFinder: ZIP extraction bypasses uploadDeny MIME filter allowing PHP file upload (RCE)
Source: CVE Program / CVE List V5
Vulnerability Description
elFinder is an open-source file manager for web, written in JavaScript using jQuery UI. Prior to 2.1.70, checkExtractItems() in php/elFinderVolumeDriver.class.php calls mimetypeInternalDetect() without passing the result through mimeTypeNormalize(). Because the .phtml, .phar, .php5, and .php3 extensions are absent from mime.types, the staticMimeMap entries that map them to text/x-php are not applied, and allowPutMime() permits extraction even when uploadDeny blocks text/x-php. An attacker with ZIP upload permission can extract PHP-executable files into a web-accessible files/ directory and achieve remote code execution when the server executes those extensions. This issue is fixed in version 2.1.70.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
危险类型文件的不加限制上传
Source: CVE Program / CVE List V5
Vulnerability Title
Studio 42 elFinder 任意文件上传漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Studio 42 elFinder是Studio 42团队的一款基于Web的文件管理组件。 Studio 42 elFinder 2.1.70之前版本存在任意文件上传漏洞，该漏洞源于未将mimetypeInternalDetect()的结果通过mimeTypeNormalize()处理，导致具有ZIP上传权限的攻击者可将PHP可执行文件提取到web可访问目录，可能导致远程代码执行。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Studio-42 elFinder < 2.1.70 -

II. Public POCs for CVE-2026-81891

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-81891

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-81891 (2)

Vendor Advisories for CVE-2026-81891 (1)

Vendor Pages for CVE-2026-81891 (1)

Same Patch Batch · Studio-42 · 2026-08-31 · 3 CVEs total

CVE-2026-81889 8.6 HIGH elFinder: SSRF protection bypass via DNS rebinding in the `fsock_get_contents()` fallback
CVE-2026-81890 5.4 MEDIUM elFinder: CSRF in netmount allows forced FTP mounts and server-side FTP connections

IV. Related Vulnerabilities

Same product: elFinder
Same vendor: Studio-42
Same weakness: CWE-434

V. Comments for CVE-2026-81891

No comments yet

Leave a comment