CVE-2020-27178 json
Improper Authentication in Apereo CAS
published 2020-10-16 6 y ago modified 2026-06-17 4 mo ago also GHSA-q39c-5vh5-vw2p , EUVD-2021-1832
- cvss
- 7.5
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.2%
- EPSS 1.2% chance of exploitation in 30 days, percentile 68%
- public exploits
- 0
- none known
Summary
Apereo CAS 5.3.x before 5.3.16, 6.x before 6.1.7.2, 6.2.x before 6.2.4, and 6.3.x before 6.3.0-RC4 mishandles secret keys with Google Authenticator for multifactor authentication.
Patch / fix
- maven org.apereo.cas:cas-server-webapp 5.3.16, 6.1.7.2, 6.2.4
- maven org.apereo.cas:cas-server-support-otp-mfa-core 5.3.16, 6.1.7.2, 6.2.4
- apereo central_authentication_service 5.3.16, 6.1.7.2, 6.2.4
Exploit prediction
1.22% chance of exploitation in the next 30 days, higher than 68% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:P/A:N |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| maven | org.apereo.cas:cas-server-webapp | >=5.3.0, <5.3.16 >=6.0.0, <6.1.7.2 >=6.2.0, <6.2.4 |
5.3.16 6.1.7.2 6.2.4 |
| maven | org.apereo.cas:cas-server-support-otp-mfa-core | >=5.3.0, <5.3.16 >=6.0.0, <6.1.7.2 >=6.2.0, <6.2.4 |
5.3.16 6.1.7.2 6.2.4 |
Classification
- Weakness
-
- CWE-287 Improper Authentication
References
-
apereo.github.io
/2020/10/14/gauthvuln/
vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2020-27178
advisory
-
apereo.github.io
/2020/10/14/gauthvuln
web
Sources
- CVE List CVE-2020-27178
- GitHub Advisory GHSA-q39c-5vh5-vw2p
- NVD CVE-2020-27178
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