CVE-2026-42197

Stored XSS in RELATE's user profile allows for admin account takeover.

• CVSS 8.7
• CWE-79
• Input Validation and Sanitization
• Remote

RELATE is a web-based courseware package. Versions prior to commit 555f0efb1c5bd7531c07cd73724d7e566a81f620 have a stored cross-site scripting vulnerability that allows any enrolled student to execute arbitrary JavaScript in an administrator's browser session, potentially leading to full admin account takeover. The `get_user()` method in `ParticipationAdmin` renders user-controlled input using `mark_safe` combined with Python's % string formatting. This bypasses Django\'s automatic HTML escaping entirely. The value returned by `get_full_name` is derived directly from the `first_name` and `last_name` fields of the User model. These fields are freely editable by any authenticated user through the profile page (`/profile/`) with no sanitization applied. When an admin views the Participation list in the Django admin panel, the unsanitized value is rendered directly into the HTML response, causing the injected script to execute in the admin's browser. Commit 555f0efb1c5bd7531c07cd73724d7e566a81f620 fixes the issue.

CVE

CVE-2026-42197

CWE

CWE-79

CVSS base score

8.7

Published

2026-05-27

OWASP

A03 Injection

Orthogonal defect classification

Checking

Code defect classification

Missing Check

Category

Input Validation and Sanitization

Subcategory

Cross-Site Scripting (XSS)

Accessibility scope

Remote

Impact

Privilege Escalation

Affected component

RELATE

Solution

Update RELATE to a version that includes commit `555f0efb1c5bd7531c07cd73724d7e566a81f620` or newer.

# In a file like 'course/admin.py' within a Django project

from django.contrib import admin
from django.utils.safestring import mark_safe

from course.models import Participation


@admin.register(Participation)
class ParticipationAdmin(admin.ModelAdmin):
    list_display = ("id", "get_user", "role")

    # The user-controlled 'first_name' and 'last_name' fields are used
    # to generate get_full_name(). The result is then formatted into
    # a string that is marked as "safe" for rendering. This allows
    # any HTML/JavaScript in the user's name to be rendered directly
    # on the admin page, causing a stored XSS vulnerability.
    def get_user(self, obj):
        return mark_safe('<a href GIVEMEANAME="%d/">%s</a>' % (
            obj.user.pk, obj.user.get_full_name()))

    get_user.short_description = 'User'
    get_user.admin_order_field = 'user'

from django.contrib import admin
from django.urls import reverse
from django.utils.html import format_html

class ParticipationAdmin(admin.ModelAdmin):
    list_display = ("id", "get_user", "course", "time_stamp")
    list_display_links = ("id",)
    list_filter = ("course",)
    search_fields = (
            "user__first_name", "user__last_name", "user__username", "user__email")
    readonly_fields = ("user", "course", "time_stamp")

    def get_user(self, participation):
        return format_html(
                '<a href="{}">{}</a>',
                reverse("admin:auth_user_change", args=(participation.user.pk,)),
                participation.user.get_full_name())
    get_user.short_description = 'User'
    get_user.admin_order_field = 'user'

<script>alert('XSS')</script>

@misc{vaitp:cve202642197,
  title        = {{Stored XSS in RELATE's user profile allows for admin account takeover.}},
  author       = {Bogaerts, Fr\'ed\'eric and Ivaki, Naghmeh and Fonseca, Jos\'e},
  year         = {2026},
  note         = {VAITP Python Vulnerability Dataset, entry CVE-2026-42197},
  howpublished = {\url{https://netpack.pt/vaitp/vulnerability/CVE-2026-42197/}}
}