CVE-2026-54263: Wagtail Cross-Site Scripting Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-23m2-mghx-vqmf",
  "modified" : "2026-08-20T18:40:26Z",
  "published" : "2026-08-20T18:40:26Z",
  "aliases" : [ "CVE-2026-54263" ],
  "summary" : "Wagtail: Reflected XSS in dynamic image URL generator view",
  "details" : "### Impact\n\nA reflected cross-site scripting (XSS) vulnerability exists on the dynamic image URL generator view within the Wagtail admin interface. A user with a limited-permission editor account for the Wagtail admin could craft a URL that, when viewed by a user with higher privileges, could perform actions with that user's credentials. The vulnerability is present for all sites, even if they do not enable the [dynamic image serve view](https://docs.wagtail.org/en/stable/advanced_topics/images/image_serve_view.html). The vulnerability is not exploitable by an ordinary site visitor without access to the Wagtail admin.\n\n### Patches\n\nPatched versions have been released as Wagtail 7.3.3 and 7.4.2.\n\n### Workarounds\n\nFor sites that cannot easily upgrade to a current supported version, the vulnerability can be patched by adding the following code to `urls.py` URL pattern declarations to override the vulnerable view. This disables the admin dynamic image preview functionality, while the public-facing dynamic image serve view still works.\n\n```python\nfrom django.http import HttpResponseBadRequest\nfrom django.urls import path\nfrom wagtail.admin import urls as wagtailadmin_urls\n\ndef disabled_output(request, image_id):\n    return HttpResponseBadRequest(\"\", content_type=\"text/plain\")\n\nurlpatterns = [\n    # Example where the CMS admin is at /admin/.\n    # Add this before the Wagtail admin URLs registration, with the same sub-path.\n    path(\"admin/images/<int:image_id>/generate_url/output/\", disabled_output),\n    path(\"admin/\", include(wagtailadmin_urls)),\n]\n```\n\n### Acknowledgements\n\nMany thanks to Thibaud Colas (@thibaudcolas) for reporting this issue.\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n\n- Visit Wagtail's [support channels](https://docs.wagtail.org/en/stable/support.html)\n- Email us at [security@wagtail.org](mailto:security@wagtail.org) (view our [security policy](https://github.com/wagtail/wagtail/security/policy) for more information).",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "wagtail"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "7.3"
      }, {
        "fixed" : "7.3.3"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "wagtail"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "7.4"
      }, {
        "fixed" : "7.4.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/wagtail/wagtail/security/advisories/GHSA-23m2-mghx-vqmf"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-54263"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/wagtail/PYSEC-2026-616.yaml"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/wagtail/wagtail"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-79" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-08-20T18:40:26Z",
    "nvd_published_at" : "2026-07-01T22:16:49Z"
  }
}