Improper Certificate Validation Affecting erlang-sasl package, versions *


Severity

Recommended
0.0
high
0
10

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.23% (14th percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-RHEL8-ERLANGSASL-17157435
  • published4 Jun 2026
  • disclosed27 May 2026

Introduced: 27 May 2026

NewCVE-2026-42789  (opens in a new tab)
CWE-295  (opens in a new tab)

How to fix?

There is no fixed version for RHEL:8 erlang-sasl.

NVD Description

Note: Versions mentioned in the description apply only to the upstream erlang-sasl package and not the erlang-sasl package as distributed by RHEL. See How to fix? for RHEL:8 relevant fixed versions and status.

Improper Following of a Certificate's Chain of Trust vulnerability in Erlang OTP public_key (pubkey_cert module) allows a non-CA certificate to be accepted as an intermediate issuer, enabling certificate chain forgery.

In lib/public_key/src/pubkey_cert.erl, pubkey_cert:validate_extensions/7 contains two flaws that together allow a certificate with basicConstraints cA:false and no keyUsage extension to be used as an intermediate issuer in a chain passed to public_key:pkix_path_validation/3: the cA:false clause recurses into the remaining extensions without rejecting the certificate when it is in issuer position, and the keyUsage check only fires when the extension is present, so a certificate lacking keyUsage entirely bypasses the keyCertSign enforcement.

Any party holding an end-entity certificate with basicConstraints cA:false and no keyUsage extension, issued by any CA in the victim's trust store, can use that certificate's private key to sign forged leaf certificates for arbitrary identities. public_key:pkix_path_validation/3 accepts the resulting chain, and by extension every TLS or mTLS endpoint built on the OTP ssl application that relies on the default verifier is affected, including server identity verification on the client side and client certificate verification on mTLS servers.

This issue affects OTP from OTP 17.0 before OTP 26.2.5.21, 27.3.4.12, 28.5.0.1, and 29.0.1 corresponding to public_key from 0.22 before 1.15.1.7, 1.17.1.3, 1.20.3.1, and 1.21.1.

CVSS Base Scores

version 3.1