CVE-2021-21424
Published: 13 May 2021
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. The ability to enumerate users was possible without relevant permissions due to different handling depending on whether the user existed or not when attempting to use the switch users functionality. We now ensure that 403s are returned whether the user exists or not if a user cannot switch to a user or if the user does not exist. The patch for this issue is available for branch 3.4.
Priority
Status
| Package | Release | Status |
|---|---|---|
|
symfony Launchpad, Ubuntu, Debian |
bionic |
Released
(3.4.6+dfsg-1ubuntu0.1+esm2)
Available with Ubuntu Pro |
| focal |
Released
(4.3.8+dfsg-1ubuntu1+esm1)
Available with Ubuntu Pro |
|
| groovy |
Ignored
(end of life)
|
|
| hirsute |
Ignored
(end of life)
|
|
| impish |
Not vulnerable
(4.4.19+dfsg-2)
|
|
| jammy |
Not vulnerable
(4.4.19+dfsg-2)
|
|
| kinetic |
Not vulnerable
(4.4.19+dfsg-2)
|
|
| lunar |
Not vulnerable
(4.4.19+dfsg-2)
|
|
| mantic |
Not vulnerable
(4.4.19+dfsg-2)
|
|
| trusty |
Does not exist
|
|
| upstream |
Released
(4.4.19+dfsg-2)
|
|
| xenial |
Not vulnerable
(code not present)
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 5.3 |
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | Low |
| Integrity impact | None |
| Availability impact | None |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
References
- https://symfony.com/blog/cve-2021-21424-prevent-user-enumeration-in-authentication-mechanisms
- https://github.com/symfony/symfony/commit/f012eee6c6034a94566dff596fe4e16dfc5d9c1f
- https://github.com/symfony/symfony/commit/2a581d22cc621b33d5464ed65c4bc2057f72f011
- https://github.com/symfony/symfony/security/advisories/GHSA-5pv8-ppvj-4h68
- https://ubuntu.com/security/notices/USN-5290-1
- https://www.cve.org/CVERecord?id=CVE-2021-21424
- NVD
- Launchpad
- Debian