CVE-2026-55075: Coder vulnerable to OIDC account takeover via email-based user matching and email_verified bypass

July 6, 2026

Two flaws in Coder’s OIDC login chained into account takeover: email-based user matching fell back to linking by email without checking for an existing link to a different IdP subject and the email_verified claim was only enforced when present as a boolean false so an absent or non-boolean claim was treated as verified.

References

github.com/advisories/GHSA-9r87-mvcw-x35f
github.com/coder/coder/pull/25712
github.com/coder/coder/pull/25713
github.com/coder/coder/security/advisories/GHSA-9r87-mvcw-x35f
nvd.nist.gov/vuln/detail/CVE-2026-55075

Code Behaviors & Features

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