CVE-2026-56223
CVE-2026-56223 is a high-severity vulnerability with a CVSS 3.x base score of 8.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.
Key facts
- Severity: High (CVSS 3.x base score 8.7)
- CVSS v4: 9.3
- EPSS exploit prediction: 0% (15th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-38737
- Weakness: CWE-287
- Published:
- Last modified:
Description
Capgo before 12.128.2 contains a cross-domain SSO account takeover vulnerability in the provision-user endpoint that allows attackers to merge arbitrary victim accounts based on email match without validating SSO provider domain authorization. An attacker with enterprise org admin access and a malicious IdP can forge SAML assertions containing victim email addresses to trigger account merge and gain full access to victim accounts, organizations, and data.
Frequently asked questions
- What is CVE-2026-56223?
- Capgo before 12.128.2 contains a cross-domain SSO account takeover vulnerability in the provision-user endpoint that allows attackers to merge arbitrary victim accounts based on email match without validating SSO provider domain authorization. An attacker with enterprise org admin access and a malicious IdP can forge SAML assertions containing victim email addresses to trigger account merge and gain full access to victim accounts, organizations, and data.
- How severe is CVE-2026-56223?
- CVE-2026-56223 has a CVSS 3.x base score of 8.7, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
- Is CVE-2026-56223 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-56223?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-56223 have an EU (EUVD) identifier?
- Yes. CVE-2026-56223 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-38737.
- When was CVE-2026-56223 published?
- CVE-2026-56223 was published on 2026-06-24 and last updated on 2026-06-25.
References
- https://github.com/Cap-go/capgo/security/advisories/GHSA-jhjh-vp9p-54fg
- https://www.vulncheck.com/advisories/capgo-account-takeover-via-cross-domain-sso-email-assertion-in-provision-user
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