CVE-2026-58227: TLS/DTLS denial of service via unbounded recursion on cross-signed peer certificate chain

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-27 · updated 2026-10-24
Weakness: CWE-674

Description

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 OTP: from 23.2 before 27.3.4.15; from 28.0 before 28.5.0.4; from 29.0 before 29.0.4 — fixed in 27.3.4.15, 28.5.0.4, 29.0.4
Erlang/Ssl: from 10.2 before 11.2.12.11; from 11.3 before 11.6.0.4; from 11.7 before 11.7.4 — fixed in 11.2.12.11, 11.6.0.4, 11.7.4

How to fix

Upgrade to a fixed version: Erlang OTP 27.3.4.15, 28.5.0.4, 29.0.4; Erlang/Ssl 11.2.12.11, 11.6.0.4, 11.7.4. Check the vendor advisory for mitigations.

References

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