Security Digest · Vulnerability record
CVE-2026-9090: Casdoor has an authentication bypass
Casdoor versions 2.362.0 and earlier contain a vulnerability that allows an attacker to bypass authentication by supplying an arbitrary signing certificate.
CVSS 9.1 Critical EPSS 0.2% · p9
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.2%, percentile 9: FIRST’s model estimates a 0.2% chance of exploitation activity in the next 30 days, higher than 9% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
github.com/casdoor/casdoor(Go) <= 1.1000.1-0.20260321120606-239e8bd69487, no fixed version listed. Check your lockfile, including transitive dependencies.
What it is
Casdoor versions 2.362.0 and earlier contain a vulnerability that allows an attacker to bypass authentication by supplying an arbitrary signing certificate. The buildSpCertificateStore function extracts the X.509 certificate directly from the incoming SAMLResponse instead of using the trusted pre-configured Identity Provider certificate, allowing an attacker to forge assertions signed with an attacker-controlled key.
From the GitHub advisory
Casdoor versions 2.362.0 and earlier contain a vulnerability that allows an attacker to bypass authentication by supplying an arbitrary signing certificate. The buildSpCertificateStore function extracts the X.509 certificate directly from the incoming SAMLResponse instead of using the trusted pre-configured Identity Provider certificate, allowing an attacker to forge assertions signed with an attacker-controlled key.
Weakness type: CWE-287.
Product: github.com/casdoor/casdoor (Go) · Assigned by: certcc · Published: 2026-05-28
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| Go | github.com/casdoor/casdoor | <= 1.1000.1-0.20260321120606-239e8bd69487 | none listed |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| Casdoor | Casdoor | <= 2.362.0 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADP | 3.1 | 9.1 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| GitHub | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.20% probability of exploitation activity in the next 30 days; percentile 9.
Timeline
- — CVE record published by certcc
- — GitHub-reviewed advisory GHSA-fwgq-j9r9-qjgr published (critical)
- — CVE record last updated
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-fwgq-j9r9-qjgr github.com
- CVE.org record CVE-2026-9090 cve.org
- NVD entry CVE-2026-9090 nvd.nist.gov
Other references from the CVE record and advisory
- kb.cert.org kb.cert.org