CVE-2026-58227: Erlang Erlang/otp

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

The Erlang/OTP ssl application does not detect cycles when reconstructing an incomplete peer certificate chain during a TLS or DTLS handshake. In ssl_certificate:handle_incomplete_chain/5, the received chain is passed to ssl_certificate:build_certificate_chain/5, which walks issuer relationships via ssl_certificate:do_certificate_chain/7 with no cycle detection and no depth limit. When the peer supplies two mutually cross-signed certificates in unordered form (A issues B, B issues A), the issuer lookup alternates between the two certificates and the pair of functions recurses indefinitely, growing the call stack and chain accumulator without bound. An unauthenticated remote attacker can send a crafted certificate chain in a TLS or DTLS Certificate handshake message to exhaust available memory and crash the BEAM node. Only a TCP connection and a partial handshake are required; no authentication or completed handshake is needed, and both TLS/DTLS servers and clients are affected when processing peer certificate messages. This issue affects OTP from OTP 23.2 before OTP 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15, corresponding to ssl from 10.2 before 11.7.4, 11.6.0.4 and 11.2.12.11.

Affected products

• Erlang Erlang/otp: from 23.2, before 27.3.4.15 (fixed in 27.3.4.15); from 28.0, before 28.5.0.4 (fixed in 28.5.0.4); from 29.0, before 29.0.4 (fixed in 29.0.4)
• Erlang Erlang/ssl: from 10.2, before 11.2.12.11 (fixed in 11.2.12.11); from 11.3, before 11.6.0.4 (fixed in 11.6.0.4); from 11.7, before 11.7.4 (fixed in 11.7.4)

Published 2026-07-27. Last modified 2026-08-10.