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Medium

AVideo has Stored Cross-Site Scripting via Markdown Comment Injection

Type: advisorySources: OSV

WWBN AVideo is an open source video platform. Prior to version 21.0, AVideo allows Markdown in video comments and uses Parsedown (v1.7.4) without Safe Mode enabled. Markdown links are not sufficiently sanitized, allowing `javascript:` URIs to be rendered as clickable links. An authenticated low-privilege attacker can post a malicious comment that injects persistent JavaScript. When another user clicks the link, the attacker can perform actions such as session hijacking, privilege escalation (including admin takeover), and data exfiltration. Version 21.0 contains a fix. As a workaround, validate and block unsafe URI schemes (e.g., `javascript:`) before rendering Markdown, and enable Parsedown Safe Mode.

Products
Not specified
Affected versions
Not specified
Fixed versions
Not specified
CVEs
CVE-2026-27568
Confirmed fixed CVEs
Not specified
Updated in this feed
8 Nov 2026, 00:54 UTC · Revision 1

Source evidence

AVideo has Stored Cross-Site Scripting via Markdown Comment Injection

core-osv · Original source

Published 24 Feb 2026, 14:53 UTC

WWBN AVideo is an open source video platform. Prior to version 21.0, AVideo allows Markdown in video comments and uses Parsedown (v1.7.4) without Safe Mode enabled. Markdown links are not sufficiently sanitized, allowing `javascript:` URIs to be rendered as clickable links. An authenticated low-privilege attacker can post a malicious comment that injects persistent JavaScript. When another user clicks the link, the attacker can perform actions such as session hijacking, privilege escalation (including admin takeover), and data exfiltration. Version 21.0 contains a fix. As a workaround, validate and block unsafe URI schemes (e.g., `javascript:`) before rendering Markdown, and enable Parsedown Safe Mode.

osv:CVE-2026-27568
Complete source record
{
  "id": "6d711ea3bb86509e61635421af630b3dfab9fff6ab9531639d562a994e65c54a",
  "url": "https://osv.dev/vulnerability/CVE-2026-27568",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "AVideo has Stored Cross-Site Scripting via Markdown Comment Injection",
    "summary": "WWBN AVideo is an open source video platform. Prior to version 21.0, AVideo allows Markdown in video comments and uses Parsedown (v1.7.4) without Safe Mode enabled. Markdown links are not sufficiently sanitized, allowing `javascript:` URIs to be rendered as clickable links. An authenticated low-privilege attacker can post a malicious comment that injects persistent JavaScript. When another user clicks the link, the attacker can perform actions such as session hijacking, privilege escalation (including admin takeover), and data exfiltration. Version 21.0 contains a fix. As a workaround, validate and block unsafe URI schemes (e.g., `javascript:`) before rendering Markdown, and enable Parsedown Safe Mode.",
    "evidence": "osv:CVE-2026-27568",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-27568",
      "aliases": [
        "CVE-2026-27568",
        "GHSA-rcqw-6466-3mv7"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/wwbn/avideo",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "ce8da5d6b641f94da5762619339263915f40fdbd"
                },
                {
                  "fixed": "ade348ed6d28b3797162c3d9e98054fb09ec51d7"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:wwbn:avideo:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "21.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "ade348ed6d28b3797162c3d9e98054fb09ec51d7"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "ce8da5d6b641f94da5762619339263915f40fdbd"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "21.0"
                  }
                ]
              }
            }
          ],
          "versions": [
            "18.0",
            "14.3.1",
            "14.3",
            "12.4",
            "11.6",
            "11.5",
            "11.1.1",
            "11.1",
            "11",
            "10.8",
            "8.9.1",
            "8.9",
            "8.7",
            "8.6",
            "8.5",
            "8.1",
            "7.8",
            "7.7",
            "7.6",
            "7.4",
            "7.3",
            "7.2",
            "4.0",
            "3.4",
            "2.7",
            "2.2"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-27568.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:52.493031013Z",
      "provider": "osv",
      "references": [
        "https://github.com/WWBN/AVideo/releases/tag/21.0",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27568.json",
        "https://github.com/WWBN/AVideo/security/advisories/GHSA-rcqw-6466-3mv7",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-27568",
        "https://github.com/WWBN/AVideo/commit/ade348ed6d28b3797162c3d9e98054fb09ec51d7"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27568.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-27568",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 521126,
  "published_at": "2026-02-24T14:53:20.826+00:00"
}