Arbitrary file upload in Vvveb Cms
CVE-2026-6257
Vvveb CMS v1.0.8.2 contains a remote code execution vulnerability in its media management functionality where a missing return statement in the file rename handler allows authenticated attackers to rename files to blocked extensions .php or .htaccess. Attackers can exploit this logic flaw by first uploading a text file and renaming it to .htaccess to inject Apache directives that register PHP-executable MIME types, then uploading another file and renaming it to .php to execute arbitrary operating system commands as the www-data user.
Vulnerability class: Unrestricted File Upload
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.009 (58.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 58.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.009 · change: +0.003
Affected products
- Vvveb Cms — versions 1.0.8, 1.0.8.2
Weakness classification (CWE)
References
- Patch Commit (patch)
- www.vulncheck.com/advisories/vvveb-cms-remote-code-execution-via-media-manageme… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-6257?
- CVE-2026-6257 is a critical-severity vulnerability in Vvveb Cms, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.1/10. Published 2026-04-20.
- How severe is CVE-2026-6257?
- Critical severity. CVSS v3 base score is 9.1 out of 10.