GHSA-wc43-73w7-x2f5
MEDIUMOry Kratos's setting required_aal `highest_available` does not properly respect code + mfa credentials
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
github.com/ory/kratosReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Preconditions
- The
codelogin method is enabled with thepasswordless_enabledflag set totrue. - A 2FA method such as
totpis enabled. required_aalof the whomai check or the settings flow is set tohighest_available. AAL stands for Authenticator Assurance Levels and can range from 0 (no factor) to 2 (two factors).- A user uses the
codemethod as the only login method available. They do not have a password or any other first factor credential enabled. - The user has 2FA enabled.
- The user’s
available_aalis incorrectly stored in the database asaal1oraal0orNULL. - A user signs in using the code method, but does not complete the 2FA challenge.
Example server configuration
Below you will find an vulnerable example configuration. Keep in mind that, for the account to be vulnerable, the account must have no first factor except the code method enabled plus a second factor.
selfservice:
methods:
code:
# The `code` login method is enabled with the `passwordless_enabled` flag set to `true`
passwordless_enabled: true
totp:
# 2FA method such as `totp` is enabled
enabled: true
flows:
settings:
# This is set
required_aal: highest_available
session:
whoami:
# Or this
required_aal: highest_available
Impact
Given the preconditions, the highest_available setting will incorrectly assume that the identity’s highest available AAL is aal1 even though it really is aal2. This means that the highest_available configuration will act as if the user has only one factor set up, for that particular user. This means that they can call the settings and whoami endpoint without a aal2 session, even though that should be disallowed.
An attacker would need to steal or guess a valid login OTP of a user who has only OTP for login enabled and who has an incorrect available_aal value stored, to exploit this vulnerability.
All other aspects of the session (e.g. the session’s aal) are not impacted by this issue.
On Ory Network, only 0,00066% of registered users were affected by this issue, and most of those users appeared to be test users. Their respective AAL values have since been updated and they are no longer vulnerable to this attack.
Patches
Version 1.3.0 is not affected by this issue.
Workarounds
If you require 2FA please disable the passwordless code login method. If that is not possible, check the sessions aal to identify if the user has aal1 or aal2.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/ory/kratos | all versions | 1.3.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/ory/kratos. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/ory/kratos to 1.3.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wc43-73w7-x2f5 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-wc43-73w7-x2f5 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-wc43-73w7-x2f5. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-wc43-73w7-x2f5 in your dependencies?
O3 detects GHSA-wc43-73w7-x2f5 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.