core-rs-albatross: Integer Underflow (Wrap or Wraparound)
CVE-2026-33184 is a high-severity integer underflow (wrap or wraparound) vulnerability in core-rs-albatross from Nimiq, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected core-rs-albatross versions: < 1.3.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.48% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of core-rs-albatross you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Nimiq | core-rs-albatross | < 1.3.0 | Not stated |
| Nimiq | Nimiq Proof-of-stake | 1.2.2 and earlier | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA (github.com).
Official description
nimiq/core-rs-albatross is a Rust implementation of the Nimiq Proof-of-Stake protocol based on the Albatross consensus algorithm. Prior to version 1.3.0, the discovery handler accepts a peer-controlled limit during handshake and stores it unchanged. The immediate HandshakeAck path then honors limit = 0 and returns zero contacts, which makes the session look benign. Later, after the same session reaches Established, the periodic update path computes self.peer_list_limit.unwrap() as usize - 1. With limit = 0, that wraps to usize::MAX and then in rand 0.9.2, choose_multiple() immediately attempts Vec::with_capacity(amount), which deterministically panics with capacity overflow. This issue has been patched in version 1.3.0.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Integer Underflow (Wrap or Wraparound)
The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.
More Integer Underflow (Wrap or Wraparound) vulnerabilities (CWE-191)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other vulnerabilities in core-rs-albatross
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 8.1 High severity
Recent Integer Underflow (Wrap or Wraparound) vulnerabilities
- 7.5 High severity
- 9.1 Critical severity
- 7.8 High severity
- 7.8 High severity
- 7.5 High severity
- 8.8 High severity
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