{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-81925", "assignerOrgId": "ff5b8ace-8b95-4078-9743-eac1ca5451de", "state": "PUBLISHED", "assignerShortName": "ConcreteCMS", "dateReserved": "2026-08-27T18:25:17.660Z", "datePublished": "2026-09-15T20:07:01.834Z", "dateUpdated": "2026-09-16T17:48:00.821Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "ff5b8ace-8b95-4078-9743-eac1ca5451de", "shortName": "ConcreteCMS", "dateUpdated": "2026-09-15T20:07:01.834Z"}, "title": "Concrete CMS below 9.5.3 is vulnerable to Reflected Cross-Site Scripting (XSS) via Conversation Custom Date Format", "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-79", "description": "CWE-79 Improper Neutralization of Input During Web Page Generation", "type": "CWE"}]}], "impacts": [{"capecId": "CAPEC-591", "descriptions": [{"lang": "en", "value": "CAPEC-591 Reflected XSS"}]}], "affected": [{"vendor": "Concrete CMS", "product": "Concrete CMS", "collectionURL": "https://github.com/concretecms/concretecms", "repo": "https://github.com/concretecms/concretecms", "versions": [{"status": "affected", "version": "5.0.0", "lessThanOrEqual": "9.5.2", "versionType": "git"}], "defaultStatus": "unaffected"}], "descriptions": [{"lang": "en", "value": "Concrete CMS before 9.5.3 improperly neutralized a user-supplied custom date format when rendering conversation messages, resulting in reflected cross-site scripting. An attacker could execute arbitrary JavaScript in the browser of a user who was tricked into submitting a crafted POST request to the conversation view endpoint. Exploitation was aided by the absence of a CSRF token on the endpoint, which allowed the payload to be delivered through an auto-submitting cross-origin POST without authentication.\u00a0The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "<p><span>Concrete CMS before 9.5.3 improperly neutralized a user-supplied custom date format when rendering conversation messages, resulting in reflected cross-site scripting. An attacker could execute arbitrary JavaScript in the browser of a user who was tricked into submitting a crafted POST request to the conversation view endpoint. Exploitation was aided by the absence of a CSRF token on the endpoint, which allowed the payload to be delivered through an auto-submitting cross-origin POST without authentication.</span>&nbsp;The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.</p>"}]}], "references": [{"url": "https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes", "tags": ["release-notes"]}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV4_0": {"attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "userInteraction": "PASSIVE", "vulnConfidentialityImpact": "LOW", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subAvailabilityImpact": "NONE", "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": "LOW", "baseScore": 2.1, "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N"}}], "credits": [{"lang": "en", "value": "tenzai", "type": "finder"}], "source": {"defect": ["HackerOne"], "advisory": "3802509", "discovery": "EXTERNAL"}, "x_generator": {"engine": "Vulnogram 1.0.5"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-09-16T17:46:17.138727Z", "id": "CVE-2026-81925", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-16T17:48:00.821Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"cna": {"title": "Concrete CMS below 9.5.3 is vulnerable to Reflected Cross-Site Scripting (XSS) via Conversation Custom Date Format", "source": {"defect": ["HackerOne"], "advisory": "3802509", "discovery": "EXTERNAL"}, "credits": [{"lang": "en", "type": "finder", "value": "tenzai"}], "impacts": [{"capecId": "CAPEC-591", "descriptions": [{"lang": "en", "value": "CAPEC-591 Reflected XSS"}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 2.1, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "LOW", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "PASSIVE", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "LOW", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"repo": "https://github.com/concretecms/concretecms", "vendor": "Concrete CMS", "product": "Concrete CMS", "versions": [{"status": "affected", "version": "5.0.0", "versionType": "git", "lessThanOrEqual": "9.5.2"}], "collectionURL": "https://github.com/concretecms/concretecms", "defaultStatus": "unaffected"}], "references": [{"url": "https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes", "tags": ["release-notes"]}], "x_generator": {"engine": "Vulnogram 1.0.5"}, "descriptions": [{"lang": "en", "value": "Concrete CMS before 9.5.3 improperly neutralized a user-supplied custom date format when rendering conversation messages, resulting in reflected cross-site scripting. An attacker could execute arbitrary JavaScript in the browser of a user who was tricked into submitting a crafted POST request to the conversation view endpoint. Exploitation was aided by the absence of a CSRF token on the endpoint, which allowed the payload to be delivered through an auto-submitting cross-origin POST without authentication.\u00a0The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.", "supportingMedia": [{"type": "text/html", "value": "<p><span>Concrete CMS before 9.5.3 improperly neutralized a user-supplied custom date format when rendering conversation messages, resulting in reflected cross-site scripting. An attacker could execute arbitrary JavaScript in the browser of a user who was tricked into submitting a crafted POST request to the conversation view endpoint. Exploitation was aided by the absence of a CSRF token on the endpoint, which allowed the payload to be delivered through an auto-submitting cross-origin POST without authentication.</span>&nbsp;The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting.</p>", "base64": false}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-79", "description": "CWE-79 Improper Neutralization of Input During Web Page Generation"}]}], "providerMetadata": {"orgId": "ff5b8ace-8b95-4078-9743-eac1ca5451de", "shortName": "ConcreteCMS", "dateUpdated": "2026-09-15T20:07:01.834Z"}}, "adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-81925", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-16T17:46:17.138727Z"}}}], "providerMetadata": {"shortName": "CISA-ADP", "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "dateUpdated": "2026-09-16T17:47:55.929Z"}}]}, "cveMetadata": {"cveId": "CVE-2026-81925", "state": "PUBLISHED", "dateUpdated": "2026-09-15T20:07:01.834Z", "dateReserved": "2026-08-27T18:25:17.660Z", "assignerOrgId": "ff5b8ace-8b95-4078-9743-eac1ca5451de", "datePublished": "2026-09-15T20:07:01.834Z", "assignerShortName": "ConcreteCMS"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"collectionURL": "https://github.com/concretecms/concretecms", "defaultStatus": "unaffected", "product": "Concrete CMS", "repo": "https://github.com/concretecms/concretecms", "vendor": "Concrete CMS", "versions": [{"lessThanOrEqual": "9.5.2", "status": "affected", "version": "5.0.0", "versionType": "git"}]}], "source": "ff5b8ace-8b95-4078-9743-eac1ca5451de"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*", "matchCriteriaId": "E66C3C40-213B-4CEE-AB69-9655764A1DBE", "versionEndExcluding": "9.5.3", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Concrete CMS before 9.5.3 improperly neutralized a user-supplied custom date format when rendering conversation messages, resulting in reflected cross-site scripting. An attacker could execute arbitrary JavaScript in the browser of a user who was tricked into submitting a crafted POST request to the conversation view endpoint. Exploitation was aided by the absence of a CSRF token on the endpoint, which allowed the payload to be delivered through an auto-submitting cross-origin POST without authentication.\u00a0The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori from Tenzai for reporting."}], "id": "CVE-2026-81925", "lastModified": "2026-09-21T17:53:13.887", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.1, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 2.7, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 2.1, "baseSeverity": "LOW", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "LOW", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/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", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "ff5b8ace-8b95-4078-9743-eac1ca5451de", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-81925", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-09-16T17:46:17.138727Z", "version": "2.0.3"}}]}, "published": "2026-09-15T20:18:04.090", "references": [{"source": "ff5b8ace-8b95-4078-9743-eac1ca5451de", "tags": ["Broken Link"], "url": "https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes"}], "sourceIdentifier": "ff5b8ace-8b95-4078-9743-eac1ca5451de", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}], "source": "ff5b8ace-8b95-4078-9743-eac1ca5451de", "type": "Secondary"}]}

{}