Improper Certificate Validation in Erlang OTP - CVE-2026-42789
Published: July 2, 2026
Vulnerability details
The vulnerability allows a remote user to spoof arbitrary certificate identities.
The vulnerability exists due to improper certificate validation in public_key:pkix_path_validation/3 when validating certificate chains. A remote user can use a non-CA end-entity certificate and its private key to forge leaf certificates for arbitrary identities to spoof arbitrary certificate identities.
Exploitation requires possession of an end-entity certificate issued by a CA in the victim's trust store where basicConstraints is set to cA:false and the keyUsage extension is absent.
Affected software
Debian Linux
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
Server Applications Module
openSUSE Leap
erlang-reltool
erlang-epmd-debuginfo
erlang-debugsource
erlang
erlang-epmd
erlang-debuginfo
erlang-dialyzer
erlang-wx-debuginfo
erlang-debugger-src
erlang-diameter
erlang-et-src
erlang-dialyzer-debuginfo
erlang-et
erlang-reltool-src
erlang-jinterface-src
erlang-diameter-src
erlang-doc
erlang-src
erlang-observer-src
erlang-jinterface
erlang-dialyzer-src
erlang-wx-src
erlang-debugger
erlang-observer
erlang-wx
erlang26-et-src
erlang26-jinterface-src
erlang26-epmd
erlang26-jinterface
erlang26-wx-src
erlang26-dialyzer-src
erlang26-diameter-src
erlang26-wx
erlang26-et
erlang26-debugger
erlang26-reltool-src
erlang26-reltool
erlang26-debugger-src
erlang26-dialyzer-debuginfo
erlang26-debugsource
erlang26-epmd-debuginfo
erlang26-doc
erlang26-diameter
erlang26-wx-debuginfo
erlang26-observer-src
erlang26-src
erlang26-debuginfo
erlang26-observer
erlang26-dialyzer
erlang26
erlang (Red Hat package)
erlang (Debian package)
How to mitigate CVE-2026-42789
erlang-reltool - update to 23.3.4.19-150300.3.39.1
erlang-epmd-debuginfo - update to 23.3.4.19-150300.3.39.1
erlang-debugsource - update to 23.3.4.19-150300.3.39.1
erlang - update to 23.3.4.19-150300.3.39.1
erlang-epmd - update to 23.3.4.19-150300.3.39.1
erlang-debuginfo - update to 23.3.4.19-150300.3.39.1
erlang-dialyzer - update to 23.3.4.19-150300.3.39.1
erlang-wx-debuginfo - update to 23.3.4.19-150300.3.39.1
erlang-debugger-src - update to 23.3.4.19-150300.3.39.1
erlang-diameter - update to 23.3.4.19-150300.3.39.1
erlang-et-src - update to 23.3.4.19-150300.3.39.1
erlang-dialyzer-debuginfo - update to 23.3.4.19-150300.3.39.1
erlang-et - update to 23.3.4.19-150300.3.39.1
erlang-reltool-src - update to 23.3.4.19-150300.3.39.1
erlang-jinterface-src - update to 23.3.4.19-150300.3.39.1
erlang-diameter-src - update to 23.3.4.19-150300.3.39.1
erlang-doc - update to 23.3.4.19-150300.3.39.1
erlang-src - update to 23.3.4.19-150300.3.39.1
erlang-observer-src - update to 23.3.4.19-150300.3.39.1
erlang-jinterface - update to 23.3.4.19-150300.3.39.1
erlang-dialyzer-src - update to 23.3.4.19-150300.3.39.1
erlang-wx-src - update to 23.3.4.19-150300.3.39.1
erlang-debugger - update to 23.3.4.19-150300.3.39.1
erlang-observer - update to 23.3.4.19-150300.3.39.1
erlang-wx - update to 23.3.4.19-150300.3.39.1
erlang26-et-src - update to 26.2.1-150300.7.28.1
erlang26-jinterface-src - update to 26.2.1-150300.7.28.1
erlang26-epmd - update to 26.2.1-150300.7.28.1
erlang26-jinterface - update to 26.2.1-150300.7.28.1
erlang26-wx-src - update to 26.2.1-150300.7.28.1
erlang26-dialyzer-src - update to 26.2.1-150300.7.28.1
erlang26-diameter-src - update to 26.2.1-150300.7.28.1
erlang26-wx - update to 26.2.1-150300.7.28.1
erlang26-et - update to 26.2.1-150300.7.28.1
erlang26-debugger - update to 26.2.1-150300.7.28.1
erlang26-reltool-src - update to 26.2.1-150300.7.28.1
erlang26-reltool - update to 26.2.1-150300.7.28.1
erlang26-debugger-src - update to 26.2.1-150300.7.28.1
erlang26-dialyzer-debuginfo - update to 26.2.1-150300.7.28.1
erlang26-debugsource - update to 26.2.1-150300.7.28.1
erlang26-epmd-debuginfo - update to 26.2.1-150300.7.28.1
erlang26-doc - update to 26.2.1-150300.7.28.1
erlang26-diameter - update to 26.2.1-150300.7.28.1
erlang26-wx-debuginfo - update to 26.2.1-150300.7.28.1
erlang26-observer-src - update to 26.2.1-150300.7.28.1
erlang26-src - update to 26.2.1-150300.7.28.1
erlang26-debuginfo - update to 26.2.1-150300.7.28.1
erlang26-observer - update to 26.2.1-150300.7.28.1
erlang26-dialyzer - update to 26.2.1-150300.7.28.1
erlang26 - update to 26.2.1-150300.7.28.1
erlang (Red Hat package) - update to 26.2.5.21-2.el9ost
erlang (Debian package) - update to 1:27.3.4.1+dfsg-1+deb13u3