CVE-2026-104436

Summary

Zebra before 4.5.0 contains an uncontrolled resource consumption vulnerability that allows remote P2P peers to exhaust blocking-pool threads by sending oversized block locator vectors. Attackers can send getblocks or getheaders messages with up to 65,535 locator hashes, triggering per-hash chain lookups that degrade block validation, RPC, and mempool performance.

Affected Software

VendorProductVersion RangeStatus
ZcashFoundationzebra0 < 4.5.0affected
ZcashFoundationzebra4.5.0unaffected
ZcashFoundationzebra0 < 8.0.0affected
ZcashFoundationzebra8.0.0unaffected

Weaknesses

  • CWE-770: Allocation of Resources Without Limits or Throttling

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References