Bitcoin Optech newsletter #411 is here:

• describes the responsible disclosure of a denial-of-service vulnerability that affected older versions of LND
• summarizes popular Q&A from Stack Exchange
• Optech Newsletter #411 Podcast
  https://bitcoinops.org/en/newsletters/2026/06/26/

Nishant Bansal posted to Delving Bitcoin disclosing a denial-of-service vulnerability he discovered through state-machine fuzzing of LND’s gossip handling...
https://bitcoinops.org/en/newsletters/2026/06/26/#lnd-zero-timestamp-gossip-dos-disclosure

Selected Q&A from Bitcoin Stack Exchange

• Is it a bug that OP_IF is part of the tapscript opcodes?
• Why would forbidding OP_IF in tapscript be a problem?
• Does a softfork always succeed?
• How to set up Bitcoin Core to mine a valid block after the BIP110 activation in August 2026?
• Are BIP110 blocks on a branch with lower difficulty valid?
• What is the story behind Bitcoin test networks?
• Why was -datacarriersize redefined in 2022, and why was the 2023 proposal to expand it not merged?
• Are chains of 26 unconfirmed transactions prohibited by the wallet in Bitcoin Core 31.0?
• Are there changes in Bitcoin Core 29.0 that affect memory usage?
• What is Bitcoin Core’s release schedule?
  https://bitcoinops.org/en/newsletters/2026/06/26/#selected-qa-from-bitcoin-stack-exchange

Bitcoin Optech will host an audio recap discussion of this newsletter streaming live on X/Twitter Tuesday at 16:30 UTC.