← Vulnerability feed

Vulnerability record · CVE-2026-55676 · published 11 August 2026

CVE-2026-55676: Unrestricted file upload vulnerability

Malcolm is a network traffic analysis tool suite. The file-upload component (FilePond PHP backend) accepts uploads at `POST /server/php/submit.php` and stores them in a directory served by the same nginx and php-fpm instance. The allow-list that should restrict accepted file types is an empty array by default (`file-upload/php/config.php:16`), so the type check is a no-op and every extension is accepted. The filename sanitizer keeps the `.php` extension intact. Committed files land in `/var/www/upload/server/php/files` (`file-upload/php/config.php:7`), and the component's nginx routes any URL ending in `.php` to php-fpm. An authenticated `GET /server/php/files/<name>.php` then executes the uploaded code as `www-data`. Prior to version 26.06.1, in RBAC mode, the upload endpoint is reachable by the granular `ROLE_UPLOAD` role (`nginx/lua/nginx_auth_helpers.lua:71`), a role intended only for submitting capture files. As a result, a user holding the upload-only role runs arbitrary PHP as `www-data` inside the file-upload container. Version 26.06.1 fixes the issue.

8.8 CVSS 3.1 High EPSS 0.51% · top 59.0% CWE-434 · Unrestricted file upload Deferred
8.8CVSS 3.1 base score
0.51%EPSS exploitation probability, 30 days
NoNot in CISA KEV
0Affected product versions listed by NVD
2References
9 Sep 2026Last modified by NVD

Description

Malcolm is a network traffic analysis tool suite. The file-upload component (FilePond PHP backend) accepts uploads at `POST /server/php/submit.php` and stores them in a directory served by the same nginx and php-fpm instance. The allow-list that should restrict accepted file types is an empty array by default (`file-upload/php/config.php:16`), so the type check is a no-op and every extension is accepted. The filename sanitizer keeps the `.php` extension intact. Committed files land in `/var/www/upload/server/php/files` (`file-upload/php/config.php:7`), and the component's nginx routes any URL ending in `.php` to php-fpm. An authenticated `GET /server/php/files/<name>.php` then executes the uploaded code as `www-data`. Prior to version 26.06.1, in RBAC mode, the upload endpoint is reachable by the granular `ROLE_UPLOAD` role (`nginx/lua/nginx_auth_helpers.lua:71`), a role intended only for submitting capture files. As a result, a user holding the upload-only role runs arbitrary PHP as `www-data` inside the file-upload container. Version 26.06.1 fixes the issue.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References

LinkTags
https://github.com/cisagov/Malcolm/releases/tag/v26.06.1
https://github.com/cisagov/Malcolm/security/advisories/GHSA-8cvp-m7pg-qrp7

Track CVE-2026-55676 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

10.0CVE-2026-56291Balbooa Forms Joomla extension unauthenticated arbitrary file upload RCEThe Balbooa Forms extension for Joomla before version 2.4.1 accepts file uploads without authentication and does not restrict file type, allowing exe…KEVEPSS 15%analysed10.0CVE-2026-48939iCagenda Joomla extension unrestricted file upload leads to PHP RCEThe iCagenda extension for Joomla fails to restrict file types in its file attachment feature, allowing arbitrary file uploads that result in PHP cod…KEVEPSS 20%analysed10.0CVE-2026-56290Joomla Page Builder CK unauthenticated file upload leads to RCEThe Joomla Page Builder CK extension before 3.6.0 allows unauthenticated arbitrary file uploads, letting an attacker place executable files on the se…KEVEPSS 31%analysed10.0CVE-2026-48908SP Page Builder for Joomla unauthenticated arbitrary file upload RCESP Page Builder for Joomla permits unauthenticated users to upload arbitrary files, which can lead to upload and execution of PHP code. The flaw is a…KEVEPSS 89%analysed9.8CVE-2024-7399Samsung MagicINFO 9 Server path traversal allows arbitrary file writeSamsung MagicINFO 9 Server before version 21.1050 contains a path traversal flaw (CWE-22) that also enables unrestricted file upload (CWE-434), letti…KEVEPSS 92%analysed7.2CVE-2025-2749Kentico Xperience path traversal and file upload lead to RCEKentico Xperience through 13.0.178 allows an authenticated Staging Sync Server user to upload arbitrary data to relative paths, enabling path travers…KEVEPSS 4.1%analysed7.2CVE-2024-7694ThreatSonar Anti-Ransomware unrestricted file upload enables command executionThreatSonar Anti-Ransomware from TeamT5 fails to properly validate the content of uploaded files (CWE-434). An attacker holding administrator privile…KEVEPSS 1.8%analysed10.0CVE-2025-52691SmarterMail unauthenticated arbitrary file upload leading to RCESmarterTools SmarterMail contains an unrestricted file upload flaw (CWE-434) that lets an unauthenticated attacker write files to any location on the…KEVEPSS 86%analysed

Source: NIST National Vulnerability Database (record CVE-2026-55676), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.