# CVE-2026-32605: Nimiq: Remote crash via off-by-one signer bounds check in proposal buffer

> An untrusted peer can crash a Nimiq validator by sending a proposal with an out-of-bounds signer index, causing a panic before signature verification.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Apr 2026
- **Updated:** 16 Apr 2026
- **Also known as:** GHSA-g99c-h7j7-rfhv

## What is CVE-2026-32605?

CVE-2026-32605 is a high-severity denial of service vulnerability in nimiq core-rs-albatross, published on 13 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### 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, an untrusted peer could crash a validator by publishing a signed tendermint proposal message where signer == validators.num_validators(). ProposalSender::send uses > instead of >= for the signer bounds check, so the equality case passes and reaches validators.get_validator_by_slot_band(signer), which panics with an out-of-bounds index before any signature verification runs. This issue has been fixed in version 1.3.0.

Weakness: CWE-193 (Off-by-one Error), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2026-32605?

It affects 1 product.


Products: Nimiq Nimiq Proof-of-Stake.

## How do I fix CVE-2026-32605?

No fix has been published for CVE-2026-32605 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-32605 being exploited?

There is no known exploitation of CVE-2026-32605 in the wild and no public exploit code.

## Other vulnerabilities in nimiq core-rs-albatross

- [CVE-2026-33471](https://insights.sbomify.com/CVE-2026-33471/): nimiq-block has skip block quorum bypass via out-of-range BitSet indices & u16 truncation (critical 9.6)
- [CVE-2026-40093](https://insights.sbomify.com/CVE-2026-40093/): nimiq-blockchain is missing a wall-clock upper bound on block timestamps (high 8.1)
- [CVE-2026-34063](https://insights.sbomify.com/CVE-2026-34063/): network-libp2p: Peer can crash the node by opening discovery protocol substream twice (high 7.5)
- [CVE-2026-34065](https://insights.sbomify.com/CVE-2026-34065/): nimiq-primitives: Node crash due to missing interlink validation in election macro block proposals (high 7.5)
- [CVE-2026-33184](https://insights.sbomify.com/CVE-2026-33184/): nimiq/core-rs-albatross: Discovery handshake limit could underflow and later provoke a deterministic overflow panic (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-32605 and fix it if it is affected.

What it is: CVE-2026-32605 is a high-severity denial of service vulnerability in nimiq core-rs-albatross, published on 13 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-32605 in the wild and no public exploit code.

Affected product: nimiq core-rs-albatross. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-32605/ (Markdown: https://insights.sbomify.com/CVE-2026-32605/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-32605
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-32605
- OSV: https://osv.dev/vulnerability/CVE-2026-32605

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-32605/
Summaries are generated and may contain mistakes; the official description above is the record.