Post-Mortem of find_and_save_rings() bug

Quick Facts Severity: HIGH if using untrusted remote daemon, MEDIUM otherwise Affected versions: GUI/CLI wallet versions v0.12.0.0 to v0.18.4.1 Impact: Sends TXIDs of outgoing transactions to daemon after first time loading wallet from file, reducing sender anonymity Fix: Update Monero CLI / GUI to v0.18.4.2 Workaround: TBD Introduction In 2018, a persistent “ring database” was added to wallet2 to solve a sender privacy problem with forks of Monero. If an enote was received before a fork occurs, and a wallet tries spending that enote after the fork occurs on both forks, the same key image will