SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-30662

ConcreteCMS v9.4.7 contains a Denial of Service (DoS) vulnerability in the File Manager component.

MEDIUM 6.5EPSS 0.29%

Does this matter?

Lower severity and a low EPSS score (0.29%). Track it; it rarely justifies an emergency change on its own.

Description

ConcreteCMS v9.4.7 contains a Denial of Service (DoS) vulnerability in the File Manager component. The 'download' method in 'concrete/controllers/backend/file.php' improperly manages memory when creating zip archives. It uses 'ZipArchive::addFromString' combined with 'file_get_contents', which loads the entire content of every selected file into PHP memory. An authenticated attacker can exploit this by requesting a bulk download of large files, triggering an Out-Of-Memory (OOM) condition that causes the PHP-FPM process to terminate (SIGSEGV) and the web server to return a 500 error.

CVSS 3.1
6.5 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.29% probability · 21th percentile
CISA KEV
Not listed
Weakness
CWE-400
Affected
concretecms/concrete cms
Source
cve@mitre.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.