| Description: | Issue summary: Some non-default TLS server configurations can cause
unbounded memory growth when processing TLSv1.3 sessions Impact
summary: An attacker may exploit certain server configurations to
trigger unbounded memory growth that would lead to a Denial of Service
This problem can occur in TLSv1.3 if the non-default SSL_OP_NO_TICKET
option is being used (but not if early_data support is also configured
and the default anti-replay protection is in use). In this case, under
certain conditions, the session cache can get into an incorrect state
and it will fail to flush properly as it fills. The session cache will
continue to grow in an unbounded manner. A malicious client could
deliberately create the scenario for this failure to force a Denial of
Service. It may also happen by accident in normal operation. This
issue only affects TLS servers supporting TLSv1.3. It does not affect
TLS clients. The FIPS modules in 3.2, 3.1 and 3.0 are not affected by
this issue. OpenSSL 1.0.2 is also not affected by this issue.
|
