What’s Vulnerable › Vulnerabilities
CVE-2026-40093: nimiq-blockchain is missing a wall-clock upper bound on block timestamps
- Severity: high (CVSS 8.1 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.3% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-04-09 · updated 2026-10-26
- Weakness: CWE-1284
Description
nimiq-blockchain provides persistent block storage for Nimiq's Rust implementation. In 1.3.0 and earlier, block timestamp validation enforces that timestamp >= parent.timestamp for non-skip blocks and timestamp == parent.timestamp + MIN_PRODUCER_TIMEOUT for skip blocks, but there is no visible upper bound check against the wall clock. A malicious block-producing validator can set block timestamps arbitrarily far in the future. This directly affects reward calculations via Policy::supply_at() and batch_delay() in blockchain/src/reward.rs, inflating the monetary supply beyond the intended emission schedule.
Affected products
- nimiq-transaction: before 1.3.0 — fixed in 1.3.0
How to fix
Upgrade to a fixed version: nimiq-transaction 1.3.0. Check the vendor advisory for mitigations.
References
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