{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-8899", "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599", "state": "PUBLISHED", "assignerShortName": "Wordfence", "dateReserved": "2026-05-18T21:10:59.140Z", "datePublished": "2026-05-27T05:31:33.290Z", "dateUpdated": "2026-05-27T10:31:31.086Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599", "shortName": "Wordfence", "dateUpdated": "2026-05-27T05:31:33.290Z"}, "affected": [{"vendor": "gapgag55", "product": "Auto Thumbnails", "versions": [{"version": "0", "status": "affected", "lessThanOrEqual": "1.0", "versionType": "semver"}], "defaultStatus": "unaffected"}], "descriptions": [{"lang": "en", "value": "The Auto Thumbnail plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'thumbnails' shortcode in all versions up to, and including, 1.0. This is due to insufficient input sanitization and output escaping on the shortcode's 'width' and 'height' attributes in the athn_thumbnails() function, which are concatenated directly into an HTML <img> tag. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page."}], "title": "Auto Thumbnails <= 1.0 - Authenticated (Contributor+) Stored Cross-Site Scripting via Shortcode Attributes", "references": [{"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/f0cc349a-96f9-4b11-a0b4-28bc4ccc022c?source=cve"}, {"url": "https://plugins.trac.wordpress.org/browser/automatic-thumbnail/tags/1.0/index.php#L34"}, {"url": "https://plugins.trac.wordpress.org/browser/automatic-thumbnail/tags/1.0/index.php#L13"}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')", "cweId": "CWE-79", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N", "baseScore": 6.4, "baseSeverity": "MEDIUM"}}], "credits": [{"lang": "en", "type": "finder", "value": "Gilang Asra Bilhadi"}], "timeline": [{"time": "2026-05-26T17:24:44.000Z", "lang": "en", "value": "Disclosed"}]}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-05-27T10:20:52.699173Z", "id": "CVE-2026-8899", "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": "2026-05-27T10:31:31.086Z"}}]}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "The Auto Thumbnail plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'thumbnails' shortcode in all versions up to, and including, 1.0. This is due to insufficient input sanitization and output escaping on the shortcode's 'width' and 'height' attributes in the athn_thumbnails() function, which are concatenated directly into an HTML <img> tag. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page."}], "id": "CVE-2026-8899", "lastModified": "2026-05-27T07:16:18.083", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.4, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 3.1, "impactScore": 2.7, "source": "security@wordfence.com", "type": "Primary"}]}, "published": "2026-05-27T07:16:18.083", "references": [{"source": "security@wordfence.com", "url": "https://plugins.trac.wordpress.org/browser/automatic-thumbnail/tags/1.0/index.php#L13"}, {"source": "security@wordfence.com", "url": "https://plugins.trac.wordpress.org/browser/automatic-thumbnail/tags/1.0/index.php#L34"}, {"source": "security@wordfence.com", "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/f0cc349a-96f9-4b11-a0b4-28bc4ccc022c?source=cve"}], "sourceIdentifier": "security@wordfence.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}], "source": "security@wordfence.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,1.0]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "Auto Thumbnails", "source": "cna", "vendor": "gapgag55"}, "product": "auto_thumbnails", "vendor": "gapgag55"}, {"configurations": [{"platform": null, "status": "unaffected", "versions": null}], "enrichment": {"confidence": 80.0, "confidence_source": "inferred", "scores": [{"score": 80.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "product": "wordpress", "vendor": "wordpress"}], "created": "2026-05-27T07:45:25.873024+00:00", "updated": "2026-05-27T10:06:49.268131+00:00", "vendors": ["gapgag55", "gapgag55$PRODUCT$auto_thumbnails", "wordpress", "wordpress$PRODUCT$wordpress"]}