| Package | Affected versions | Patched versions |
|---|---|---|
| github.com/coder/coder | all versions | |
| github.com/coder/coder/v2 | ≥ 2.30.0, < 2.32.7≥ 2.33.0, < 2.33.8≥ 2.34.0, < 2.34.2< 2.29.17 | 2.32.72.33.82.34.22.29.17 |
| coder | ≥ 2.30.0, < 2.32.7≥ 2.33.0, < 2.33.8≥ 2.34.0, < 2.34.2< 2.29.17 | 2.32.72.33.82.34.22.29.17 |
Coder's OIDC callback checked email_verified with a direct Go bool type assertion. When an IdP returned the claim as a non-boolean (for example the string "false") or omitted it, the assertion failed open and the email was treated as verified. Combined with an unconditional email-based account fallback, this enabled account takeover.
An attacker who registered a victim's email at a compatible IdP without verifying it could log in via OIDC and be matched to the victim's existing Coder account, receiving a session for that account. No prior authentication to Coder was required and the result was full account takeover.
The fix coerces email_verified across bool, string and numeric types (fail-closed) and blocks the email fallback when the matched user already has a different linked IdP subject.
The fix was backported to all supported release lines:
| Release line | Patched version |
|---|---|
| 2.34 | v2.34.2 |
| 2.33 | v2.33.8 |
| 2.32 | v2.32.7 |
| 2.29 (ESR) | v2.29.17 |
Ensure the IdP returns email_verified as a native JSON boolean. The email-fallback linking issue has no configuration workaround; upgrading is required.
Coder would like to thank Anthropic's Security Team (ANT-2026-22444) for independently disclosing this issue!
Running one of these products? Scan your site to see whether it exposes a vulnerable version.
Scan my site free