CVE-2020-5226 Cross-site scripting in SimpleSAMLphp
Attackers can inject HTML into error report emails via unescaped fields when using the legacy PHP template, potentially leading to XSS.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2020-5226?
CVE-2020-5226 is a medium-severity cross-site scripting vulnerability in SimpleSAMLphp, published on 24 Jan 2020. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
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.
Weakness: CWE-79
Which versions are affected by CVE-2020-5226?
2 open source packages ship an affected version, including simplesamlphp/simplesamlphp. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
simplesamlphp/simplesamlphp Packagist | From 1.18.0 | 1.18.4 |
simplesamlphp/simplesamlphp Packagist | From 1.18.0 | 1.18.4 |
Products include Simplesamlphp Simplesamlphp.
How do I fix CVE-2020-5226?
Upgrade simplesamlphp/simplesamlphp to 1.18.4 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2020-5226 being exploited?
There is no known exploitation of CVE-2020-5226 in the wild and no public exploit code.
Other vulnerabilities in SimpleSAMLphp
- CVE-2017-12868 SimpleSAMLphp Session fixation issue and authentication bypass in the authcrypt module
- CVE-2018-7644 SimpleSAMLphp Improper Verification of Cryptographic Signature
- CVE-2026-49284 SimpleSAMLphp SP accepts a response from an unexpected IdP when unsigned `Response/InResponseTo` is combined with a signed assertion lacking `SubjectConfirmationData/InResponseTo`
- CVE-2018-6520 SimpleSAMLphp Open redirection protection bypass
- CVE-2017-12870 SimpleSAMLphp Unauthenticated encryption in CBC mode
Sources
Also known as DEBIAN-CVE-2020-5226, GHSA-mj9p-v2r8-wf8w.