CVE-2026-52736
ZEBRA is a Zcash node written entirely in Rust. Prior to 4.5.0, a remote unauthenticated P2P peer can stall a Zebra node by racing an invalid block body against the valid canonical body for the same block header hash. ZIP-244 permits the attacker to mutate coinbase scriptSig authentication data while retaining the transaction identifiers, merkle root, and block header hash, so the poisoned body fails later commitment validation but shares the canonical hash. In zebra-state/src/service.rs, queue_and_commit_to_non_finalized_state recorded the hash in non_finalized_block_write_sent_hashes before contextual validation completed and did not remove it when the write task rejected the body. When the honest body later arrived, the cached hash caused KnownBlock::WriteChannel duplicate handling to suppress it, leaving the node stuck one height behind until restart or reorganization. This issue is fixed in version 4.5.0.
Scoring
- Severity
- HIGH
- CVSS base score
- 8.7
- CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
- EPSS probability
- 0.44%
- CWE
- CWE-459
- Published
- 2026-08-18
- Last modified
- 2026-08-18
Affected products
- ZcashFoundation zebra
Weakness type
Related vulnerabilities
- CVE-2026-87549 — Incomplete cleanup in Downloads in Google Chrome prior to 153.0.8010.36 allowed a remote attacker...
- CVE-2026-87436 — Incomplete cleanup in Browser in Google Chrome prior to 153.0.8010.36 allowed a remote attacker...
- CVE-2026-87446 — Incomplete cleanup in Extensions in Google Chrome prior to 153.0.8010.36 allowed a remote attacker...
- CVE-2026-85043 — Incomplete cleanup in Network in Google Chrome prior to 152.0.7977.82 allowed a remote attacker to...
- CVE-2026-78600 — Incomplete Cleanup in Elastic Cloud on Kubernetes Leading to Unauthorized Cross-Namespace Credential Retention
- CVE-2026-77037 — multer vulnerable to Denial of Service via file descriptor leak on aborted uploads
- CVE-2026-82237 — filebrowser through 2.63.23 Stale Share Link via File Rename
- CVE-2026-82236 — File Browser 2.63.6 through 2.63.23 Share Link Exposure via File Deletion