{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-55876",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-06-17T16:59:42.759Z",
        "datePublished": "2026-10-15T17:23:07.781Z",
        "dateUpdated": "2026-10-15T17:23:07.781Z"
    },
    "containers": {
        "cna": {
            "title": "Helium: Stored XSS via Unrestricted SVG File Upload — Authenticated Users Can Store Executable Scripts",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-79",
                            "lang": "en",
                            "description": "CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "NONE",
                        "baseScore": 3.5,
                        "baseSeverity": "LOW",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "LOW",
                        "privilegesRequired": "LOW",
                        "scope": "UNCHANGED",
                        "userInteraction": "REQUIRED",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/HeliumEdu/platform/security/advisories/GHSA-7r65-76fw-ch5c",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/HeliumEdu/platform/security/advisories/GHSA-7r65-76fw-ch5c"
                },
                {
                    "name": "https://github.com/HeliumEdu/platform/commit/f0de5c985c701942758b805a3d11dfb008a6af88",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/HeliumEdu/platform/commit/f0de5c985c701942758b805a3d11dfb008a6af88"
                }
            ],
            "affected": [
                {
                    "vendor": "HeliumEdu",
                    "product": "platform",
                    "versions": [
                        {
                            "version": "< 2.2.60",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-10-15T17:23:07.781Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Helium is a free online student planner for classes, homework, grades, and notes. Prior to 2.2.60, the POST /planner/attachments/ endpoint allows authenticated users to upload SVG and HTML attachments because conf/configs/common.py omits those formats from BLOCKED_ATTACHMENT_EXTENSIONS and BLOCKED_ATTACHMENT_MIME_TYPES, and helium/planner/serializers/attachmentserializer.py relies on those blocklists. An uploaded SVG served as image/svg+xml can execute embedded script when a visitor opens its public attachment URL, allowing persistent attacker-controlled active content and phishing under an application-managed storage URL. The attachment storage uses a separate origin from the application, so same-origin policy prevents the script from reading application cookies or storage, and application-session compromise is not supported by the maintained deployment configuration. This issue is fixed in version 2.2.60."
                }
            ],
            "source": {
                "advisory": "GHSA-7r65-76fw-ch5c",
                "discovery": "UNKNOWN"
            }
        }
    }
}