High severity · published Jul 28, 2026
CVE-2026-63301
Denial of Service in Quick.CMS
7.0
CVSS
0.6%
EPSS
No
On KEV
Description
In Quick.CMS, the administrative user interface restricts deletion of the primary language by omitting the corresponding option from the interface; however, the underlying language-deletion API endpoint does not enforce an equivalent server-side authorization check. As a result, an authenticated administrator can bypass the UI-level restriction and delete the primary language by sending a direct HTTP request to the API endpoint. Successful deletion of the primary language results in a Denial of Service (DoS) of application. Critically, when combined with a separate Cross-Site Request Forgery (CSRF) vulnerability (CVE-2026-1468) an unauthenticated remote attacker can craft a malicious link, which if visited by an authenticated administrator, will trigger the DoS condition without direct access to the application The vendor assessed the likelihood of exploitation as very low and determined that a fix is not necessary.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 47% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
QU
Quick.CMS · OpenSolution
through 6.8.0 · source: vendor
Affected product
QU
Quick.CMS
OpenSolution
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