Red Hat Keycloak before version 2.5.1 has an implementation of HMAC verification for JWS tokens that uses a method that runs in non-constant time, potentially leaving the application vulnerable to timing attacks.
rhn.redhat.com/errata/RHSA-2017-0876.html
access.redhat.com/errata/RHSA-2017:0872
access.redhat.com/errata/RHSA-2017:0873
bugzilla.redhat.com/show_bug.cgi?id=1412376
github.com/advisories/GHSA-w6gv-3r3v-gwgj
nvd.nist.gov/vuln/detail/CVE-2017-2585
web.archive.org/web/20170420113802/www.securitytracker.com/id/1038180
web.archive.org/web/20200227175650/www.securityfocus.com/bid/97393