In FreeRADIUS 3.0.x before 3.0.20, the EAP-pwd module used a global OpenSSL BN_CTX instance to handle all handshakes. This mean multiple threads use the same BN_CTX instance concurrently, resulting in crashes when concurrent EAP-pwd handshakes are initiated. This can be abused by an adversary as a Denial-of-Service (DoS) attack.

References

• https://nvd.nist.gov/vuln/detail/CVE-2019-17185
• https://freeradius.org/security/
• https://github.com/FreeRADIUS/freeradius-server/releases/tag/release_3_0_20
• http://lists.opensuse.org/opensuse-security-announce/2020-04/msg00039.html