CVE-2026-52731: medium-severity vulnerability in ZcashFoundation zebra
ZEBRA: Full node denial of service via non-ASCII LongPollId in getblocktemplate
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.5epss 0.5%
ZEBRA is a Zcash node written entirely in Rust. Prior to 4.5.0, an attacker authenticated to an enabled Zebra RPC endpoint can terminate zebrad by supplying a getblocktemplate LongPollId containing multi-byte UTF-8 characters. In zebra-rpc/src/methods/types/long_poll.rs, LongPollId::from_str originally checked the input byte length and then sliced fixed byte ranges to parse encoded fields. A slice boundary can land inside a multi-byte character and trigger Rust's byte index is not a char boundary panic. Zebra release builds use panic equals abort, so one malformed authenticated RPC request terminates the entire node process and can be repeated after restart. This issue is fixed in version 4.5.0.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Related CVEs — ZcashFoundation zebra
In the same product, most dangerous first.
CVE-2026-34202CRITICALZebra node crash — V5 transaction hash panic (P2P reachable)EPSS 0.8%CVE-2026-52736HIGHZEBRA: Block suppression via NU5 same-header body poisoning of sent-hash cacheEPSS 0.6%CVE-2026-52829HIGHZEBRA: IPv4-Mapped Mempool Misbehavior Update Aborts Zebra Address BookEPSS 0.6%CVE-2026-52739MEDIUMZEBRA: Repeated Non-Finalized Shielded Transaction Aborts Zebra Before Duplicate-Nullifier RejectionEPSS 0.5%CVE-2026-52732MEDIUMZEBRA: Mempool transaction admission denial via single-peer inbound queue saturationEPSS 0.5%CVE-2026-52738MEDIUMZEBRA: Finalized address balance credit-first overflow on consensus-valid blocksEPSS 0.5%