CVE-2026-32700 Devise has a confirmable "change email" race condition that permits user to confirm email they have no access to
Attackers can confirm email addresses they do not own via a race condition in Devise's Confirmable module, potentially taking over accounts.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-32700?
CVE-2026-32700 is a medium-severity vulnerability in heartcombo devise, published on 18 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Devise is an authentication solution for Rails based on Warden. Prior to version 5.0.3, a race condition in Devise's Confirmable module allows an attacker to confirm an email address they do not own. This affects any Devise application using the `reconfirmable` option (the default when using Confirmable with email changes). By sending two concurrent email change requests, an attacker can desynchronize the `confirmation_token` and `unconfirmed_email` fields. The confirmation token is sent to an email the attacker controls, but the `unconfirmed_email` in the database points to a victim's email address. When the attacker uses the token, the victim's email is confirmed on the attacker's account. This is patched in Devise v5.0.3. Users should upgrade as soon as possible. As a workaround, applications can override a specific method from Devise models to force `unconfirmed_email` to be persisted when unchanged. Note that Mongoid does not seem to respect that `will_change!` should force the attribute to be persisted, even if it did not really change, so the user might have to implement a workaround similar to Devise by setting `changed_attributes["unconfirmed_email"] = nil` as well.
Weakness: CWE-362
Which versions are affected by CVE-2026-32700?
2 open source packages ship an affected version, including devise. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
devise RubyGems | All versions | 5.0.3 |
devise RubyGems | All versions | 5.0.3 |
Products include Heartcombo Devise.
How do I fix CVE-2026-32700?
Upgrade devise to 5.0.3 or later.
Is CVE-2026-32700 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-32700 exists.
Other vulnerabilities in heartcombo devise
Sources
Also known as DEBIAN-CVE-2026-32700, GHSA-57hq-95w6-v4fc, UBUNTU-CVE-2026-32700.