Auth bypass in Capgo
CVE-2026-56312
Capgo before 12.128.2 contains an improper validation vulnerability in the accept_invitation endpoint that creates user accounts before captcha validation is enforced. Attackers can bypass captcha protection by sending POST requests with invalid captcha tokens to create unwanted accounts and burn invite links.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L.
EPSS exploit prediction
EPSS: 0.004 (29.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 29.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Capgo — versions 0, 12.128.2
Weakness classification (CWE)
References
- github.com/Cap-go/capgo/security/advisories/GHSA-whc5-fvr7-g5v3 (vendor-advisory)
- www.vulncheck.com/advisories/capgo-account-creation-before-captcha-validation-i… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-56312?
- CVE-2026-56312 is a medium-severity vulnerability in Capgo, classified under Improper Authentication. CVSS score: 6.5/10. Published 2026-07-10.
- How severe is CVE-2026-56312?
- Medium severity. CVSS v3 base score is 6.5 out of 10.