CVE-2026-18526

{"id": "CVE-2026-18526", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-18526", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-08-21T16:04:14.531056Z"}}], "cvssMetricV40": [{"type": "Secondary", "source": "help@fluidattacks.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 7.4, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "HIGH", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:N/SC:L/SI:L/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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "PASSIVE", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "subIntegrityImpact": "LOW", "vulnIntegrityImpact": "HIGH", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "LOW", "vulnConfidentialityImpact": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "help@fluidattacks.com", "affectedData": [{"repo": "https://github.com/humhub/humhub", "vendor": "HumHub", "product": "HumHub", "versions": [{"status": "affected", "version": "1.18.4"}], "platforms": ["Windows", "MacOS", "Linux"], "defaultStatus": "unaffected"}]}], "published": "2026-08-19T15:16:58.010", "references": [{"url": "https://fluidattacks.com/advisories/greeicy", "source": "help@fluidattacks.com"}, {"url": "https://github.com/humhub/humhub", "source": "help@fluidattacks.com"}, {"url": "https://github.com/humhub/humhub/pull/8373", "source": "help@fluidattacks.com"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "help@fluidattacks.com", "description": [{"lang": "en", "value": "CWE-79"}]}], "descriptions": [{"lang": "en", "value": "HumHub Community Edition 1.18.4 and 1.18.4-pl1 contain a stored Cross-Site Scripting (XSS) vulnerability in the oEmbed confirmation rendering workflow."}], "lastModified": "2026-08-28T15:31:31.210", "sourceIdentifier": "help@fluidattacks.com"}