{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-8134","assignerOrgId":"ff5b8ace-8b95-4078-9743-eac1ca5451de","state":"PUBLISHED","assignerShortName":"ConcreteCMS","dateReserved":"2026-05-07T17:49:33.331Z","datePublished":"2026-05-21T20:13:31.343Z","dateUpdated":"2026-05-22T12:15:15.179Z"},"containers":{"cna":{"providerMetadata":{"orgId":"ff5b8ace-8b95-4078-9743-eac1ca5451de","shortName":"ConcreteCMS","dateUpdated":"2026-05-21T20:13:31.343Z"},"title":"Concrete CMS 9.5.0 and below is vulnerable to Authenticated RCE via Composer customTemplate Path Traversal leading to PHP File Inclusion","problemTypes":[{"descriptions":[{"lang":"en","cweId":"CWE-98","description":"CWE-98 Improper control of filename for Include/Require statement in PHP program ('PHP remote file inclusion')","type":"CWE"}]},{"descriptions":[{"lang":"en","cweId":"CWE-434","description":"CWE-434 Unrestricted upload of file with dangerous type","type":"CWE"}]},{"descriptions":[{"lang":"en","cweId":"CWE-23","description":"CWE-23 Relative path traversal","type":"CWE"}]}],"impacts":[{"capecId":"CAPEC-252","descriptions":[{"lang":"en","value":"CAPEC-252 PHP Local File Inclusion"}]}],"affected":[{"vendor":"Concrete CMS","product":"Concrete CMS","collectionURL":"https://github.com/concretecms/concretecms","repo":"https://github.com/concretecms/concretecms","programFiles":["https://github.com/concretecms/concretecms"],"versions":[{"status":"affected","version":"5.0","lessThanOrEqual":"9.5.0","versionType":"git"}],"defaultStatus":"unaffected"}],"descriptions":[{"lang":"en","value":"Concrete CMS 9.5.0 and below fails to sanitize path traversal sequences in the ptComposerFormLayoutSetControlCustomTemplate field when saving page type composer form layouts. An authenticated rogue administrator with composer form editing rights can exploit this to include arbitrary readable files on the server. Combined with the file uploader's extension-only validation (which permits PHP code in files saved with image extensions like .png), this can result in authenticated remote code execution. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 9.4 with vector CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H   Thanks Yonatan Drori (Tenzai) for reporting.","supportingMedia":[{"type":"text/html","base64":false,"value":"<div>Concrete CMS 9.5.0 and below fails to sanitize path traversal sequences in the <code>ptComposerFormLayoutSetControlCustomTemplate</code> field when saving page type composer form layouts. An authenticated rogue administrator with composer form editing rights can exploit this to include arbitrary readable files on the server. Combined with the file uploader's extension-only validation (which permits PHP code in files saved with image extensions like <code>.png</code>), this can result in&nbsp;authenticated remote code execution.&nbsp;The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 9.4 with vector&nbsp;CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H&nbsp; &nbsp;Thanks&nbsp;<span>Yonatan Drori&nbsp;</span>(Tenzai)&nbsp;<span>for reporting.&nbsp;</span></div>"}]}],"references":[{"url":"https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes","tags":["release-notes"]}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"HIGH","userInteraction":"NONE","vulnConfidentialityImpact":"HIGH","subConfidentialityImpact":"HIGH","vulnIntegrityImpact":"HIGH","subIntegrityImpact":"HIGH","vulnAvailabilityImpact":"HIGH","subAvailabilityImpact":"HIGH","exploitMaturity":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED","version":"4.0","baseSeverity":"CRITICAL","baseScore":9.4,"vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H"}}],"credits":[{"lang":"en","value":"Yonatan Drori (Tenzai)","type":"finder"}],"source":{"defect":["HackerOne"],"discovery":"UNKNOWN"},"x_generator":{"engine":"Vulnogram 1.0.2"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-22T12:15:06.851749Z","id":"CVE-2026-8134","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-05-22T12:15:15.179Z"}}]}}