XSS in Simplesamlphp
CVE-2020-5226
Cross-site scripting in SimpleSAMLphp before version 1.18.4. The www/erroreport.php script allows error reports to be submitted and sent to the system administrator. Starting with SimpleSAMLphp 1.18.0, a new SimpleSAML\Utils\EMail class was introduced to handle sending emails, implemented as a wrapper of an external dependency. This new wrapper allows us to use Twig templates in order to create the email sent with an error report. Since Twig provides automatic escaping of variables, manual escaping of the free-text field in www/errorreport.php was removed to avoid double escaping. However, for those not using the new user interface yet, an email template is hardcoded into the class itself in plain PHP. Since no escaping is provided in this template, it is then possible to inject HTML inside the template by manually crafting the contents of the free-text field.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.005 (42.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N.
Affected products
- Simplesamlphp — versions >= 1.18.0, < 1.18.4
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
- security-advisories@github.com (x_refsource_MISC, Vendor Advisory)
Frequently asked questions
- What is CVE-2020-5226?
- CVE-2020-5226 is a medium-severity vulnerability in Simplesamlphp, classified under Cross-site Scripting. CVSS score: 4.4/10. Published 2020-01-24.
- How severe is CVE-2020-5226?
- Medium severity. CVSS v3 base score is 4.4 out of 10.