CVE-2021-22904 Possible DoS Vulnerability in Action Controller Token Authentication
Attackers can cause denial of service in Ruby on Rails applications using token authentication due to a vulnerable regular expression.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-22904?
CVE-2021-22904 is a high-severity denial of service vulnerability in Rubyonrails Rails, published on 11 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The actionpack ruby gem before 6.1.3.2, 6.0.3.7, 5.2.4.6, 5.2.6 suffers from a possible denial of service vulnerability in the Token Authentication logic in Action Controller due to a too permissive regular expression. Impacted code uses `authenticate_or_request_with_http_token` or `authenticate_with_http_token` for request authentication.
Weakness: CWE-400
Which versions are affected by CVE-2021-22904?
8 open source packages ship an affected version, including actionpack. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
actionpack RubyGems | From 4.0.0 | 5.2.4.6 |
actionpack RubyGems | From 4.0.0 | 5.2.4.6 |
actionpack RubyGems | From 5.2.5 | 5.2.6 |
actionpack RubyGems | From 5.2.5 | 5.2.6 |
actionpack RubyGems | From 6.0.0 | 6.0.3.7 |
actionpack RubyGems | From 6.0.0 | 6.0.3.7 |
2 more packages
actionpack RubyGems | From 6.1.0 | 6.1.3.2 |
actionpack RubyGems | From 6.1.0 | 6.1.3.2 |
Products include Rubyonrails Rails.
How do I fix CVE-2021-22904?
Upgrade actionpack to a fixed version for your release line: 5.2.4.6, 5.2.6, 6.0.3.7 or 6.1.3.2.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2021-22904 being exploited?
There is no known exploitation of CVE-2021-22904 in the wild and no public exploit code.
Other vulnerabilities in Rubyonrails Rails
- CVE-2013-0277 Active Record contains deserialization of arbitrary YAML
- CVE-2017-17916 SQL injection in n/a
- CVE-2017-17917 SQL injection in n/a
- CVE-2026-33195 Rails Active Storage has possible Path Traversal in DiskService
- CVE-2024-26142 Rails possible ReDoS vulnerability in Accept header parsing in Action Dispatch
Sources
Also known as DEBIAN-CVE-2021-22904, GHSA-7wjx-3g7j-8584, OESA-2021-1248, UBUNTU-CVE-2021-22904.