CVE-2020-27178 Improper Authentication in Apereo CAS

What is CVE-2020-27178?

CVE-2020-27178 is a high-severity authentication bypass vulnerability in n/a, published on 16 Oct 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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.

Which versions are affected by CVE-2020-27178?

12 open source packages ship an affected version, including org.apereo.cas:cas-server-support-otp-mfa-core and org.apereo.cas:cas-server-webapp. It affects 1 product.

Products include Apereo Central Authentication Service.

How do I fix CVE-2020-27178?

Upgrade org.apereo.cas:cas-server-support-otp-mfa-core to a fixed version for your release line: 5.3.16, 6.1.7.2 or 6.2.4.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2020-27178 being exploited?

There is no known exploitation of CVE-2020-27178 in the wild and no public exploit code.

Other vulnerabilities in n/a

• CVE-2023-4612 MFA bypass in Apereo CAS Critical 9.8
• CVE-2024-4399 CAS <= 1.0.0 - Unauthenticated SSRF Critical 9.1
• CVE-2019-10754 Use of Insufficiently Random Values in Apereo CAS High 8.1
• CVE-2015-1169 Auth bypass in n/a High 7.5
• CVE-2024-11208 Apereo CAS login session expiration Medium 6.3

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-q39c-5vh5-vw2p.