vulnerability / NVI-00002496 / Revision 1
Grav: 2FA Bypass via 'login.regenerate2FASecret' - Secret Rotation During Pending Challenge
OSV carries this publisher advisory for getgrav/grav. This is an aggregated source copy; consult the original publisher and compare update dates.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
getgrav/grav
source listedECOSYSTEM: introduced 0; fixed 2.0.4
### Summary When 2FA is enabled on an account, submitting correct credentials authenticates the user but leaves them unauthorized pending TOTP verification. During this pending-challenge window, the `login.regenerate2FASecret` task which requires only `$user->exists()`, not `$user->authorized` can be called without a CSRF nonce. It overwrites the victim's `twofa_secret` on disk with an attacker-chosen value, returns the new secret in the JSON response, and the attacker computes a valid TOTP code to complete the 2FA flow. The second factor is **reduced to password-only**. The exploit was confirmed live after enabling 2FA to a user. ### Details Four code locations in login plugin v3.8.10 enable the chain: **1. Session user set even with 2FA pending** `user/plugins/login/login.php` - `userLogin()` assigns `$session->user = $user` before TOTP verification completes. This makes `$this->grav['user']` point to the victim in the pending-challenge window. **2. `taskRegenerate2FASecret` - no authorization check** `user/plugins/login/classes/Controller.php` ```php public function taskRegenerate2FASecret() { $user = $this->grav['user']; if ($user->exists()) {
03 / Response
What to do next
- vendor patch
The original advisory lists fixed boundaries 2.0.4 for getgrav/grav. Confirm the publisher’s latest guidance.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-7mgc-c7pq-3rr3 ↗
GitHub Advisory Database via OSV · vendor advisory
Observed . GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.