CVE-2026-42764
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk47th percentile - higher than 47% of all known CVEs
Summary
Receiving a QUIC initial packet with an invalid token may trigger a NULL pointer dereference in the OpenSSL QUIC server with address validation disabled, leading to abnormal termination of the server process and Denial of Service.
Risk Assessment
An attacker can crash the server by sending an initial packet with an invalid or expired token, potentially causing service outages.
Recommendation
It is recommended not to disable address validation in the OpenSSL QUIC server configuration to avoid this vulnerability. Also, avoid using the SSL_LISTENER_FLAG_NO_VALIDATE flag.
Original NVD description (English source)
Issue summary: Receiving a QUIC initial packet with an invalid token may trigger a NULL pointer dereference in the OpenSSL QUIC server with address validation disabled. Impact summary: NULL pointer dereference typically causes abnormal termination of the affected QUIC server process and a Denial of Service. If the address validation is disabled in the OpenSSL QUIC server implementation, an attacker can crash the server by sending an initial packet with an invalid or expired token. By default, the client address validation is enabled in the OpenSSL QUIC server implementation, which makes the default configuration not vulnerable to this issue. However if the SSL_LISTENER_FLAG_NO_VALIDATE is used with the SSL_new_listener() call, the address validation is disabled making the vulnerable code reachable. The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.