Patch Package:           OTP 27.3.4.16
Git Tag:                 OTP-27.3.4.16
Date:                    2026-08-04
Trouble Report Id:       OTP-20137, OTP-20275
Seq num:                 GH-11402, PR-11110, PR-11409
System:                  OTP
Release:                 27
Application:             erts-15.2.7.12, ssh-5.2.11.11
Predecessor:             OTP 27.3.4.15

Check out the git tag OTP-27.3.4.16, and build a full OTP system including
documentation. Apply one or more applications from this build as patches to your
installation using the ‘otp_patch_apply’ tool. For information on install
requirements, see descriptions for each application version below.

erts-15.2.7.12

The erts-15.2.7.12 application can be applied independently of other
applications on a full OTP 27 installation.

Fixed Bugs and Malfunctions

• Fixed a regression in the previous patch release that prevented epmd from
  binding to localhost.

  Own Id: OTP-20275
  Related Id(s): GH-11402, PR-11409

Full runtime dependencies of erts-15.2.7.12

kernel-9.0, sasl-3.3, stdlib-4.1

ssh-5.2.11.11

The ssh-5.2.11.11 application can be applied independently of other applications
on a full OTP 27 installation.

Fixed Bugs and Malfunctions

• The SSH client and server now reject incoming packets not aligned to the
  cipher block size as required by RFC 4253 §6. For CBC ciphers, a timing-safe
  “packet discard” mechanism (CVE-2008-5161 mitigation) ensures structural
  errors are indistinguishable from MAC failures before disconnecting. AEAD and
  encrypt-then-MAC modes disconnect immediately.

  Own Id: OTP-20137
  Related Id(s): PR-11110

Full runtime dependencies of ssh-5.2.11.11

crypto-5.0, erts-14.0, kernel-9.0, public_key-1.6.1, runtime_tools-1.15.1,
stdlib-5.0, stdlib-6.0

Original announcement: