CVE-2026-122006rubyonrails Active Storage insecure default
CVE-2026-122006 is a insecure default in rubyonrails Active Storage, rated critical (9.8 on CVSS 3.1).
Why this priority: Critical, and reachable over the network without an account.
Published · Updated · NVD status: Received
What it is
The product's default setting is unsafe and many installs keep it.
How it is reached
An attacker can exploit it over the network, without an account, and nobody has to click anything.
What an attacker gains
A successful attack can read the data it protects, change data or behaviour and take it offline. In practice, this kind of flaw lets an attacker use a weak default the deployment never changed.
Is it being exploited?
There is no public report of exploitation yet. It can be exploited automatically, at scale. EPSS estimates a 0.74% chance of exploitation activity in the next 30 days, higher than 55% of scored CVEs.
What to do
- Upgrade rubyonrails Active Storage to a fixed version for your release line (8.0.5.2, 8.1.4.1).
- Until it is patched, keep it off the internet or behind a VPN, allowlist or authenticating proxy.
Description from NVD
The activestorage gem before 8.1.4.1 for Ruby on Rails, when ImageMagick attachment processing occurs, can allow server read and write operations (e.g., reading secret_key_base) because the ImageMagick analyzer runs when a file is attached, and there is not an ImageMagick security policy to block unintended functionality.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Default settings, permissions and deployment configuration. The flaw sits between the shipped defaults and a hardened deployment.
Trust boundaries in play
- Internet-facing entry points. No account is needed. Any instance reachable from outside your perimeter, through a load balancer, gateway, VPN or exposed admin port, is in scope.
- Between the shipped defaults and a hardened deployment. An attacker who crosses it can use a weak default the deployment never changed.
Questions to answer about your own systems
- Where does rubyonrails Active Storage run in your systems, and at which version?
- Which of those instances can be reached from the internet or partner networks?
- What can it reach once compromised: which data stores, secrets and services?
Read more
Patches and commits
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.