Path Traversal in Quick.CMS

published 2026-07-28 3mo ago modified 2026-10-24 18d ago also EUVD-2026-49756

cvss: 5.1; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.6%; EPSS 0.6% chance of exploitation in 30 days, percentile 47%
public exploits: 0; none known

A Path Traversal vulnerability exists in Quick.CMS through the URI path component of HTTP requests, where the server fails to normalize dot-dot-slash (../) sequences before resolving and serving the requested file. An authenticated attacker with admin privileges can use this vulnerability to read contents of files located in the sibling directory of the webroot via a crafted HTTP request containing ../ sequences in the URI.

The vendor assessed the likelihood of exploitation as very low and determined that a fix is not necessary.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 3mo ago (2026-07-28)

Exploit prediction

0.57% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by	version	score	vector
CNA	4.0	5.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N
CNA	4.0	5.1	CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

OpenSolution Quick.CMS

Classification

Weakness

CWE-23 Relative Path Traversal

References

cert.pl /en/posts/2026/07/CVE-2026-63301
third-party-advisory
opensolution.org /
product

Sources

CVE List CVE-2026-63303
NVD CVE-2026-63303

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