The Erlang otp TLS server answers with different TLS alerts to different error types in the RSA PKCS #1 1.5 padding. This allows an attacker to decrypt content or sign messages with the server's private key (this is a variation of the Bleichenbacher attack).
An issue was discovered in Erlang/OTP 18.x. Erlang's generation of compiled regular expressions is vulnerable to a heap overflow. Regular expressions using a malformed extpattern can indirectly specify an offset that is used as an array index. This ordinal permits arbitrary regions within the erts_alloc arena to be both read and written to.
Erlang/OTP before 18.0-rc1 does not properly check CBC padding bytes when terminating connections, which makes it easier for man-in-the-middle attackers to obtain cleartext data via a padding-oracle attack, a variant of CVE-2014-3566 (aka POODLE).
The random number generator in the Crypto application before 2.0.2.2, and SSH before 2.0.5, as used in the Erlang/OTP ssh library before R14B03, uses predictable seeds based on the current time, which makes it easier for remote attackers to guess DSA host and SSH session keys.