CVE-2026-33195 Rails Active Storage has possible Path Traversal in DiskService
Attackers can read, write, or delete arbitrary server files via path traversal in Rails Active Storage DiskService if user input is used as blob keys.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-33195?
CVE-2026-33195 is a high-severity path traversal vulnerability in Rubyonrails Rails, published on 23 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Active Storage allows users to attach cloud and local files in Rails applications. Prior to versions 8.1.2.1, 8.0.4.1, and 7.2.3.1, Active Storage's `DiskService#path_for` does not validate that the resolved filesystem path remains within the storage root directory. If a blob key containing path traversal sequences (e.g. `../`) is used, it could allow reading, writing, or deleting arbitrary files on the server. Blob keys are expected to be trusted strings, but some applications could be passing user input as keys and would be affected. Versions 8.1.2.1, 8.0.4.1, and 7.2.3.1 contain a patch.
Weakness: CWE-22
Which versions are affected by CVE-2026-33195?
6 open source packages ship an affected version, including activestorage. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
activestorage RubyGems | All versions | 7.2.3.1 |
activestorage RubyGems | All versions | 7.2.3.1 |
activestorage RubyGems | From 8.0.0.beta1 | 8.0.4.1 |
activestorage RubyGems | From 8.0.0.beta1 | 8.0.4.1 |
activestorage RubyGems | From 8.1.0.beta1 | 8.1.2.1 |
activestorage RubyGems | From 8.1.0.beta1 | 8.1.2.1 |
Products include Rubyonrails Rails.
How do I fix CVE-2026-33195?
Upgrade activestorage to a fixed version for your release line: 7.2.3.1, 8.0.4.1 or 8.1.2.1.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-33195 being exploited?
There is no known exploitation of CVE-2026-33195 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-2024-26142 Rails possible ReDoS vulnerability in Accept header parsing in Action Dispatch
- CVE-2023-22792 ReDoS based DoS vulnerability in Action Dispatch
Sources
Also known as DEBIAN-CVE-2026-33195, GHSA-9xrj-h377-fr87, UBUNTU-CVE-2026-33195.