RADIUS Protocol under RFC 2865 is susceptible to forgery attacks by a local attacker who can modify any valid Response (Access-Accept, Access-Reject, or Access-Challenge) to any other response using a chosen-prefix collision attack against MD5 Response Authenticator signature.

A flaw was found in freeradius. A malicious RADIUS client or home server can send a malformed abinary attribute which can cause the server to crash.

In freeradius, when an EAP-SIM supplicant sends an unknown SIM option, the server will try to look that option up in the internal dictionaries. This lookup will fail, but the SIM code will not check for that failure. Instead, it will dereference a NULL pointer, and cause the server to crash.

In freeradius, the EAP-PWD function compute_password_element() leaks information about the password which allows an attacker to substantially reduce the size of an offline dictionary attack.

It was discovered freeradius up to and including version 3.0.19 does not correctly configure logrotate, allowing a local attacker who already has control of the radiusd user to escalate his privileges to root, by tricking logrotate into writing a radiusd-writable file to a directory normally inaccessible by the radiusd user. NOTE: the upstream software maintainer has stated "there is simply no way for anyone to gain privileges through this alleged issue."

FreeRADIUS before 3.0.19 mishandles the "each participant verifies that the received scalar is within a range, and that the received group element is a valid point on the curve being used" protection mechanism, aka a "Dragonblood" issue, a similar issue to CVE-2019-9498 and CVE-2019-9499.

FreeRADIUS before 3.0.19 does not prevent use of reflection for authentication spoofing, aka a "Dragonblood" issue, a similar issue to CVE-2019-9497.

An FR-GV-206 issue in FreeRADIUS 2.x before 2.2.10 and 3.x before 3.0.15 allows "DHCP - Read overflow when decoding option 63" and a denial of service.

An FR-GV-205 issue in FreeRADIUS 2.x before 2.2.10 allows "DHCP - Buffer over-read in fr_dhcp_decode_options()" and a denial of service.

An FR-GV-204 issue in FreeRADIUS 2.x before 2.2.10 allows "DHCP - Memory leak in fr_dhcp_decode()" and a denial of service.

An FR-GV-203 issue in FreeRADIUS 2.x before 2.2.10 allows "DHCP - Memory leak in decode_tlv()" and a denial of service.

An FR-GV-202 issue in FreeRADIUS 2.x before 2.2.10 allows "Write overflow in rad_coalesce()" - this allows remote attackers to cause a denial of service (daemon crash) or possibly execute arbitrary code.

An FR-GV-201 issue in FreeRADIUS 2.x before 2.2.10 and 3.x before 3.0.15 allows "Read / write overflow in make_secret()" and a denial of service.

FreeRADIUS 2.2.x before 2.2.8 and 3.0.x before 3.0.9 does not properly check revocation of intermediate CA certificates.

modules/rlm_unix/rlm_unix.c in FreeRADIUS before 2.2.0, when unix mode is enabled for user authentication, does not properly check the password expiration in /etc/shadow, which allows remote authenticated users to authenticate using an expired password.

FreeRADIUS RADIUS server allows remote attackers to cause a denial of service (CPU consumption) via a flood of Access-Request packets.