CVE-2026-85271
Open edX Platform: Stored CSS Injection in Email Digest Notifications via Unsanitized Thread Title (incomplete patch of CVE-2026-42857)
Description
Open edX Platform enables the authoring and delivery of online learning at any scale. From Redwood until Ulmo and Verawood.1, the add_additional_attributes_to_notifications function in openedx/core/djangoapps/notifications/email/utils.py assigns notification content without sanitizing discussion-title values produced by get_notification_content in openedx/core/djangoapps/notifications/base_notification.py. An enrolled student can place CSS-capable markup in the post_title value supplied by lms/djangoapps/discussion/rest_api/discussions_notifications.py. Digest and batched-email rendering then passes that value through openedx/core/djangoapps/notifications/templates/notifications/digest_content.html as safe HTML, allowing email-open tracking and content spoofing or phishing when another learner opens a CSS-rendering client. The immediate-email path is not affected because it strips title markup and renders a separately sanitized body. This issue is fixed in Ulmo and Verawood.1.
INFO
Published Date :
Sept. 18, 2026, 9:18 p.m.
Last Modified :
Sept. 18, 2026, 9:18 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-85271
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Ensure user input for 'discussion-title' is properly sanitized.
- Review email rendering logic for unescaped HTML content.
- Apply security patches for Open edX Platform versions.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-85271.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-85271 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-85271
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-85271 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-85271 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Sep. 18, 2026
Action Type Old Value New Value Added Description Open edX Platform enables the authoring and delivery of online learning at any scale. From Redwood until Ulmo and Verawood.1, the add_additional_attributes_to_notifications function in openedx/core/djangoapps/notifications/email/utils.py assigns notification content without sanitizing discussion-title values produced by get_notification_content in openedx/core/djangoapps/notifications/base_notification.py. An enrolled student can place CSS-capable markup in the post_title value supplied by lms/djangoapps/discussion/rest_api/discussions_notifications.py. Digest and batched-email rendering then passes that value through openedx/core/djangoapps/notifications/templates/notifications/digest_content.html as safe HTML, allowing email-open tracking and content spoofing or phishing when another learner opens a CSS-rendering client. The immediate-email path is not affected because it strips title markup and renders a separately sanitized body. This issue is fixed in Ulmo and Verawood.1. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Added CWE CWE-79 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/85xxx/CVE-2026-85271.json">CVE-2026-85271</a> Added Reference https://github.com/openedx/openedx-platform/commit/2af03d21b4142e53e375c7f3699b313e92ec5121 Added Reference https://github.com/openedx/openedx-platform/commit/52f2b3bb3e6fac2601c29e8f926c81498d20bb0b Added Reference https://github.com/openedx/openedx-platform/commit/5eae6e51a8797cd3b87cc132f5de73d52561c4d7 Added Reference https://github.com/openedx/openedx-platform/releases/tag/release/ulmo.4 Added Reference https://github.com/openedx/openedx-platform/releases/tag/release/verawood.1 Added Reference https://github.com/openedx/openedx-platform/security/advisories/GHSA-rv5w-f4r5-h77g