First-order effects

• Crackers now hold the full set of real-world LinkedIn passwords as a training corpus, letting them build dictionaries and rule sets tuned to how actual users chose passwords in that era.
• Any LinkedIn user whose password from 2012 was reused elsewhere is immediately exposed, since the plaintext-equivalent material is now public rather than gated behind a paid marketplace listing.

Second-order effects

• The same dynamic raises the value of adjacent old-breach dumps: the claimed Myspace trove and the Last.fm 2012 hack, where 96% of hashed passwords were cracked within two hours, become easier to finish because cross-site password reuse means each cracked corpus feeds the next.
• Services with large legacy user bases face forced credential resets and stronger login checks, since attackers can automate reuse of the newly public LinkedIn passwords against them.

Third-order effects

• Breaches stop being point-in-time events: a weakly hashed dump keeps paying out for years, so the cost of an old breach compounds as it becomes raw material for cracking every future one.
• If the pattern holds, the burden shifts toward slower, salted-per-user hashing and faster forced rotation as the baseline defense, because the attacker side now industrializes every leak into permanent infrastructure.