DTLS listener crash via race condition in dtls_packet_demux causes denial of service for all sessions

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AZL-95663 CVE-2026-55950 affecting package erlang for versions less than 26.2.5.21-6

Time-of-check Time-of-use TOCTOU race condition vulnerability in Erlang/OTP ssl dtlspacketdemux module allows an unauthenticated remote attacker to crash all active DTLS sessions on a listener. A DTLS server listener uses a single shared dtlspacketdemux genserver process to route incoming UDP...

CVE-2026-55950: Time-of-check Time-of-use (TOCTOU) Race Condition

Time-of-check Time-of-use TOCTOU race condition vulnerability in Erlang/OTP ssl dtlspacketdemux module allows an unauthenticated remote attacker to crash all active DTLS sessions on a listener. A DTLS server listener uses a single shared dtlspacketdemux genserver process to route incoming UDP...