🛡️ CVE-2026-42857
🟡 CVSS 4.6 — Medium ⚠️ Exploit Public CWE-79 NVD
4.6
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Open edX Platform enables the authoring and delivery of online learning at any scale. The HTML sanitizer clean_thread_html_body() used for discussion notification emails fails to remove tags from user-generated discussion post content. This content is rendered with Django's |safe template filter in email notification templates, allowing any enrolled student to inject arbitrary CSS into email notifications sent to other users. This enables email tracking (IP address disclosure), content spoofing, and phishing attacks. This vulnerability is fixed with commit cddc25cd791bb78f76833896e4778f668861df12.

Details

Severity MEDIUM
CVSS Score 4.6
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
CWE CWE-79
Public Exploit ⚠️ Yes
Source NVD
Published 2026-05-11
Updated 2026-06-02
Modified 2026-05-13

Affected Packages

Software From version Fixed in
openedx 2026-04-24
unknown

Similar Threats

Site Security Check

Concerned your site may already be targeted?

BotEraser analyzes incoming traffic patterns and helps identify bot behavior consistent with known exploit attempts.

Check My Site Free →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.