CVE-2026-18424 Details
Concrete CMS 9.0.0 to 9.5.2 is vulnerable to Server-Side Request Forgery iremote file import via cross-port reuse of a host's validated DNS pin. When multiple remote URLs share the same host, only the first `ValidatedRemoteUrl` is retained and reused for every later URL with that host. A low-privileged authenticated user permitted to import files could therefore supply a DNS-rebinding host that resolved to a public address during validation and to a private or loopback address during the unpinned download, causing the server to fetch internal-only resources such as loopback services, internal admin panels, or cloud metadata endpoints and to save the responses into the file manager. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N. Thanks Ahmad Wicaksono (sonix03) for reporting.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2026-18424
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
0.25 Probability of exploitation activity being observed over the next 30 days (16th percentile)
CVSS score for CVE-2026-18424
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
7.1 High
Products affected by CVE-2026-18424
ConcreteCMS 9.0.0
ConcreteCMS 9.0.1
ConcreteCMS 9.0.2
ConcreteCMS 9.1.0
ConcreteCMS 9.1.1
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Low
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CVE-2026-18424 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 506 56.41%
DE 114 12.71%
JP 92 10.26%
NL 37 4.12%
GB 37 4.12%
AU 18 2.01%
DK 16 1.78%
CH 12 1.34%
FR 10 1.11%
CA 10 1.11%

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CVE-2026-18424 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Technology 786 88.51%
Telecommunications 42 4.73%
Education 31 3.49%
Business Services 21 2.36%
Government/Politics 3 0.34%
Finance 3 0.34%
Transportation 2 0.23%

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