CVE-2019-18886 User enumeration leak using switch user functionality in Symfony
Attackers can enumerate valid users by observing differences in response handling during unauthorized user switching attempts in the Symfony security component.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2019-18886?
CVE-2019-18886 is a medium-severity vulnerability in Sensiolabs Symfony, published on 21 Nov 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An issue was discovered in Symfony 4.2.0 to 4.2.11 and 4.3.0 to 4.3.7. The ability to enumerate users was possible due to different handling depending on whether the user existed when making unauthorized attempts to use the switch users functionality. This is related to symfony/security.
Weakness: CWE-203
Which versions are affected by CVE-2019-18886?
8 open source packages ship an affected version, including symfony/security-http and symfony/symfony. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
symfony/security-http Packagist | From 4.1.0 | 4.2.12 |
symfony/security-http Packagist | From 4.1.0 | 4.2.12 |
symfony/security-http Packagist | From 4.3.0 | 4.3.8 |
symfony/security-http Packagist | From 4.3.0 | 4.3.8 |
symfony/symfony Packagist | From 4.1.0 | 4.2.12 |
symfony/symfony Packagist | From 4.1.0 | 4.2.12 |
2 more packages
symfony/symfony Packagist | From 4.3.0 | 4.3.8 |
symfony/symfony Packagist | From 4.3.0 | 4.3.8 |
Products include Sensiolabs Symfony.
How do I fix CVE-2019-18886?
Upgrade symfony/security-http to a fixed version for your release line: 4.2.12 or 4.3.8.
Is CVE-2019-18886 being exploited?
There is no known exploitation of CVE-2019-18886 in the wild and no public exploit code.
Other vulnerabilities in Sensiolabs Symfony
Sources
Also known as DEBIAN-CVE-2019-18886, GHSA-4vpc-5jx4-cfqg.