The ecc_256_modp function in ecc-256.c in Nettle before 3.2 does not properly handle carry propagation and produces incorrect output in its implementation of the P-256 NIST elliptic curve, which allows attackers to have unspecified impact via unknown vectors, a different vulnerability than CVE-2015-8805.
https://lists.lysator.liu.se/pipermail/nettle-bugs/2015/003028.html
https://lists.gnu.org/archive/html/info-gnu/2016-01/msg00006.html
https://git.lysator.liu.se/nettle/nettle/commit/c71d2c9d20eeebb985e3872e4550137209e3ce4d
http://www.ubuntu.com/usn/USN-2897-1
http://www.openwall.com/lists/oss-security/2016/02/03/1
http://www.openwall.com/lists/oss-security/2016/02/02/2
http://rhn.redhat.com/errata/RHSA-2016-2582.html
http://lists.opensuse.org/opensuse-updates/2016-02/msg00100.html
http://lists.opensuse.org/opensuse-updates/2016-02/msg00093.html
http://lists.opensuse.org/opensuse-updates/2016-02/msg00091.html
http://lists.fedoraproject.org/pipermail/package-announce/2016-February/177473.html
http://lists.fedoraproject.org/pipermail/package-announce/2016-February/177229.html
http://lists.fedoraproject.org/pipermail/package-announce/2016-February/176807.html