CVE-2026-55076 — Coder's OIDC email_verified type coercion bypass enables account takeover via unverified email linking
Coder allows organizations to provision remote development environments via Terraform. Prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, 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. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 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. As a workaround, ensure the IdP returns `email_verified` as a native JSON boolean. The email-fallback linking issue has no configuration workaround; upgrading is required.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — github.com (NIST National Vulnerability Database)
- Documented patch — github.com (NIST National Vulnerability Database)
- Documented patch — github.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Coder Coder).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (authentication), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Coder | Coder | < 2.29.17≥ 2.30.0 and < 2.32.7≥ 2.33.0 and < 2.33.8≥ 2.34.0 and < 2.34.2 | Vulnerable | NIST National Vulnerability Database |
| Coder | Coder | version >= 2.34.0, < 2.34.2version >= 2.33.0, < 2.33.8version >= 2.30.0, < 2.32.7version < 2.29.17 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.4 | CVSS 3.1 | High | 2.2 | 5.2 | security-advisories@github.com via NIST National Vulnerability Database |
| 7.4 | CVSS 3.1 | High | — | — | GitHub_M via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N (score shown at the top: security-advisories@github.com) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Review authentication logs: logins without MFA, anomalous sessions and recently created accounts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · coder/coder
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 7.4
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
7 on the record
- github.com/coder/coder/security/advisories/GHSA-75vm-6w67-gwvp
- github.com/coder/coder/pull/25713
- github.com/coder/coder/pull/25712
- github.com/coder/coder/releases/tag/v2.32.7
- github.com/coder/coder/releases/tag/v2.29.17
- github.com/coder/coder/releases/tag/v2.34.2
- github.com/coder/coder/releases/tag/v2.33.8
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-55438 Coder's workspace app CORS origin check can be bypassed via UUID-based subdomain spoofing Jul 7, 2026
- Medium CVE-2026-55437 Coder vulnerable to stored HTML injection via workspace agent logs in AgentLogLine component Jul 7, 2026
- Medium CVE-2026-55432 Coder's sub-agent app registration bypasses template port-sharing policy enforcement Jul 7, 2026
- Medium CVE-2026-55430 Coder's subdomain workspace app routing trusts unauthenticated X-Forwarded-Host header, enabling cross-app data access Jul 7, 2026
- Medium CVE-2026-55431 Coder's session token leaked to arbitrary hosts via `coder open app` for external workspace apps Jul 7, 2026
- Medium CVE-2026-55433 Coder: Devcontainer recreate endpoint missing write authorization allows read-only roles to destroy containers Jul 7, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No FIRST EPSS score.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-55076 is "Coder's OIDC email_verified type coercion bypass enables account takeover via unverified email linking", rated High. It affects Coder (Coder); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.4 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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