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SATWEI
Security notice

CVE-2019-25220 - Memory DoS due to headers spam

Original on bitcoincore.org

Source
Bitcoin Corebitcoincore.org
Originally published
Original length
5 min read
Language
English

SATWEI summary

Chains of low-difficulty headers could remotely crash Bitcoin Core nodes before v24.0.1, and one crafted chain could be reused against any node on the network. The fix in #25717 makes a node check that a chain carries enough work before storing it, which also ended reliance on checkpoints against known attacks. Severity: High.

Tags

  • CVE
  • Mining

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