CVE-2026-55076High· 7.4▾ TwilightCoder's OIDC email_verified type coercion bypass enables account takeover via unverified email linking
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 40.7 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Jul 8.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via GHSA
0.5%
0.5% → 0.6%
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:
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!
github.com/coder/coder/v2 >= 2.34.0, < 2.34.2github.com/coder/coder/v2 >= 2.33.0, < 2.33.8github.com/coder/coder/v2 >= 2.30.0, < 2.32.7github.com/coder/coder/v2 < 2.29.17Upgrade to a patched release:
github.com/coder/coder/v2 2.34.2github.com/coder/coder/v2 2.33.8github.com/coder/coder/v2 2.32.7github.com/coder/coder/v2 2.29.17Connected by shared product, vendor, weakness, or advisory.
CVE-2026-55075High· 7.4Coder vulnerable to OIDC account takeover via email-based user matching and email_verified bypass
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GHSA-qrwj-vh9x-gw5vHigh· 8.3Coder's workspace agent API insecure redirect handling allowed cross-agent file read and write
CVE-2026-55077High· 7.2Coder: User-admin role can reset owner account password