View at Official ubuntu advisory, NVD, CVE.org · CVE detail
Freshness: upstream tracker timestamp is available; use API updated time as primary recency signal.
CVE-2015-7940 low priority: Ubuntu including 1 source packages (bouncycastle), 10 status rows across 10 suites (artful, bionic, precise, trusty, upstream, vivid, wily, xenial, yakkety, zesty): ignored 5, not-affected 3, released 2.
The Bouncy Castle Java library before 1.51 does not validate a point is withing the elliptic curve, which makes it easier for remote attackers to obtain private keys via a series of crafted elliptic curve Diffie Hellman (ECDH) key exchanges, aka an "invalid curve attack."