VIR Vulnerability Intelligence Relay

CVE-2026-8203

medium
Published 2026-05-21 · Modified 2026-05-26
💬 Discuss on Community ✚ Propose mitigation
CVSS v3
5.4
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
CVSS v4 NEW
7.3
CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/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
VIR risk
5.4

Description

Concrete CMS 9.5.0 and below has Stored XSS on the height parameter. The controller does not validate or sanitize $height. Any user with editor privileges can inject malicious JavaScript that executes in the context of any visitor's browser, potentially leading to session hijacking, credential theft, or other malicious actions. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 7.3 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks Alfin Joseph for reporting.

Predictions

Exploit likelihood
64%
Patch ETA
—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Application impact
VendorProductVersionsFixed
concretecmsconcrete_cms{"endIncluding":"9.5.0"}

References

CWEs

CWE-79

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.