CVE-2026-18424 (GCVE-0-2026-18424)

Vulnerability from cvelistv5 – Published: 2026-09-15 19:49 – Updated: 2026-09-20 00:45
VLAI
Title
Concrete CMS 9.0.0 to 9.5.2 is vulnerable to SSRF protection bypass in remote file import when multiple URLs share a host but use different ports
Summary
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.
Severity
2.1 (Low)
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-20 00:41 UTC
CWE
  • CWE-918 - Server-Side request forgery (SSRF)
Assigner
ConcreteCMS CNA under the mitre root
CNA scorecard B 84/100 over 111 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Concrete CMS Concrete CMS Affected: 9.0.0 , ≤ 9.5.2 (git)
guessed Create a notification for this product.
Credits
lith004
Show details on NVD website
To clipboard 

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