CVE-2026-8337
published 2026-05-21CVE-2026-8337: Concrete CMS 9.5.0 and below is vulnerable to IDOR in surveys. To be vulnerable, a site would have to be configured in such a way that both public and private…
PriorityP431medium5.3CVSS 3.1
AVNACLPRNUINSUCNILAN
EPSS
0.19%
9.3th percentile
Concrete CMS 9.5.0 and below is vulnerable to IDOR in surveys. To be vulnerable, a site would have to be configured in such a way that both public and private surveys are present on the site. An unauthenticated attacker can vote in the restricted survey by submitting the restricted optionID through the public survey’s endpoint. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Zer0daySec https://github.com/Zee99y for reporting
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| concrete5 | concrete5 | >= 0 < 9.5.1 | 9.5.1 |
| concrete_cms | concrete_cms | 5.0 – 9.5.0 | — |
| concretecms | concrete_cms | < 9.5.1 | 9.5.1 |
CVSS provenance
nvdv3.15.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
nvdv4.06.3MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/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
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GHSA
Concrete CMS is vulnerable to IDOR in surveys
ghsa·2026-05-22
CVE-2026-8337 [MEDIUM] CWE-565 Concrete CMS is vulnerable to IDOR in surveys
Concrete CMS is vulnerable to IDOR in surveys
Concrete CMS 9.5.0 and below is vulnerable to IDOR in surveys. To be vulnerable, a site would have to be configured in such a way that both public and private surveys are present on the site. An unauthenticated attacker can vote in the restricted survey by submitting the restricted optionID through the public survey’s endpoint.
GHSA
GHSA-8c7c-h7px-267g: Concrete CMS 9
ghsa_unreviewed·2026-05-22
CVE-2026-8337 [MEDIUM] CWE-565 GHSA-8c7c-h7px-267g: Concrete CMS 9
Concrete CMS 9.5.0 and below is vulnerable to IDOR in surveys. To be vulnerable, a site would have to be configured in such a way that both public and private surveys are present on the site. An unauthenticated attacker can vote in the restricted survey by submitting the restricted optionID through the public survey’s endpoint. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Zer0daySec https://github.com/Zee99y for reporting
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-05-21
Published