Integer overflow in Nimiq Nimiq-Account
CVE-2026-34064
nimiq-account contains account primitives to be used in Nimiq's Rust implementation. Prior to version 1.3.0, `VestingContract::can_change_balance` returns `AccountError::InsufficientFunds` when `new_balance < min_cap`, but it constructs the error using `balance: self.balance - min_cap`. `Coin::sub` panics on underflow, so if an attacker can reach a state where `min_cap > balance`, the node crashes while trying to return an error. The `min_cap > balance` precondition is attacker-reachable because the vesting contract creation data (32-byte format) allows encoding `total_amount` without validating `total_amount <= transaction.value` (the real contract balance). After creating such a vesting contract, the attacker can broadcast an outgoing transaction to trigger the panic during mempool admission and block processing. The patch for this vulnerability is included as part of v1.3.0. No known workarounds are available.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (19.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 20th percentile — 19.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.003 · change: -0.002
Affected products
- Nimiq Nimiq-Account — versions < 1.3.0
- Nimiq Proof-Of-Stake
Weakness classification (CWE)
References
- github.com/nimiq/core-rs-albatross/security/advisories/GHSA-vc34-39q2-m6q3 (Patch, Vendor Advisory)
- github.com/nimiq/core-rs-albatross/pull/3658 (Patch, Issue Tracking)
- github.com/nimiq/core-rs-albatross/commit/4d01946f0b3d6c6e31786f91cdfb3eb902908… (Patch)
- github.com/nimiq/core-rs-albatross/releases/tag/v1.3.0 (Release Notes)
Frequently asked questions
- What is CVE-2026-34064?
- CVE-2026-34064 is a medium-severity vulnerability in Nimiq Nimiq-Account, classified under Integer Underflow. CVSS score: 5.3/10. Published 2026-04-22.
- How severe is CVE-2026-34064?
- Medium severity. CVSS v3 base score is 5.3 out of 10.