csirt@kutim:~/threat-intel/cve/CVE-2026-55950

Katalog CVE

CVSS 5.9 · Medium EPSS 0,38%

Kerentanan Time-of-check Time-of-use (TOCTOU) Race Condition pada erlang/otp, erlang/ssl. Skor CVSS 3.1 5.9 (Medium) menurut NVD.

Deskripsi (NVD)

Time-of-check Time-of-use (TOCTOU) race condition vulnerability in Erlang/OTP ssl (dtls_packet_demux module) allows an unauthenticated remote attacker to crash all active DTLS sessions on a listener. A DTLS server listener uses a single shared dtls_packet_demux gen_server process to route incoming UDP datagrams to the correct connection handler. When a DTLS client reconnects rapidly from the same source address and port (sending multiple ClientHello messages in quick succession), a race condition in the demux's internal gb_trees key-value store causes a {key_exists, {old, Client}} crash, terminating the demux process. Because the demux is shared across all DTLS associations on that listener, its crash immediately kills every active DTLS session, not just the attacker's. The attack is pre-authentication: the attacker only needs to send UDP datagrams containing valid ClientHello messages from the same source IP and port before the intermediate DOWN monitor message is processed by the gen_server. No credentials, no completed handshake, and no special configuration are required, and the crash can be repeated indefinitely to create a persistent denial of service for all clients of that listener. This vulnerability is associated with program file lib/ssl/src/dtls_packet_demux.erl. This issue affects OTP from OTP 25.3 before OTP 29.0.3, OTP 28.5.0.3 and OTP 27.3.4.14, corresponding to ssl from 10.9 before 11.7.3, 11.6.0.3 and 11.2.12.10.

Rincian

Terbit di NVD
2 Juli 2026
Terakhir diubah
24 Juli 2026
Status NVD
Modified
CVSS 3.1
5.9 (Medium), sumber NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-367: Time-of-check Time-of-use (TOCTOU) Race Condition
EPSS (30 hari)
0,38% peluang dieksploitasi; lebih tinggi dari 30,0% CVE lain

Produk dan versi terdampak

VendorProdukVersi terdampak
erlang erlang/otp Versi 25.3 hingga sebelum 27.3.4.14
erlang erlang/otp Versi 28.0 hingga sebelum 28.5.0.3
erlang erlang/otp Versi 29.0 hingga sebelum 29.0.3
erlang erlang/ssl Versi 10.9 hingga sebelum 11.2.12.10
erlang erlang/ssl Versi 11.3 hingga sebelum 11.6.0.3
erlang erlang/ssl Versi 11.7 hingga sebelum 11.7.3

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 5 Okt 2026, 20:11 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.