Coder's OIDC authentication allows email with partially matching domain to register

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.2 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

EPSS

• CVE-2024-27918: 0.97% estimated exploitation activity in the next 30 days; percentile 61.74 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A vulnerability in Coder's OIDC authentication could allow an attacker to bypass the CODEROIDCEMAILDOMAIN verification and create an account with an email not in the allowlist. Deployments are only affected if the OIDC provider allows users to create accounts on the provider (such as public providers like google.com). Details During OIDC registration, the user's email was improperly validated against the allowed CODEROIDCEMAILDOMAINs. This could allow a user with a domain that only partially matched an allowed domain to successfully login or register (e.g. user@exploitcorp.com would match the allowed domain corp.com). An attacker could register a domain name that exploited this vulnerability and register on a Coder instance with a public OIDC provider. Impact Coder instances with OIDC enabled and protected by the CODEROIDCEMAILDOMAIN configuration. Coder instances using a private OIDC provider are not affected, as arbitrary users cannot register through a private OIDC…

Published by the source

4 Mar 2024, 20:45 UTC

Last modified by the source

21 Mar 2024, 18:29 UTC

Source last checked

26 Oct 2026, 15:03 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-7cc2-r658-7xpf

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2024-27918

Advisory: Coder's OIDC authentication allows email with partially matching domain to register
IDs: CVE-2024-27918, GHSA-7cc2-r658-7xpf
Record: https://patchnext.com/advisories/cve-2024-27918 (revision 1, source checked 26 Oct 2026, 15:03 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.2)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Partial vendor fix; fixed versions by package: github.com/coder/coder/v2 2.8.4, 2.7.3, 2.6.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/coder/coder: affected <= 0.27.3
- Go github.com/coder/coder/v2: affected >= 2.8.0, < 2.8.4; >= 2.7.0, < 2.7.3; < 2.6.1; fixed in 2.7.3, 2.8.4, 2.6.1

## Suggested inspection (read-only)
- Go github.com/coder/coder: check the installed version with your package manager.
- Go github.com/coder/coder/v2: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/coder/coder, github.com/coder/coder/v2.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-7cc2-r658-7xpf (GitHub-reviewed advisory GHSA-7cc2-r658-7xpf lists affected ranges: Go github.com/coder/coder/v2 >=2.8.0 =2.7.0 =0 =0 <=0.27.3)

Commands are suggestions: review each one before running it.