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.
CVE-2026-104436
CVSS base score
3.7 (v3.1)
Severity
LOW
Attack vector
Network
Weakness
CWE-770
Last modified
October 29, 2026
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L