CVE-2026-34066: nimiq-blockchain Peer-triggerable Panic During History Sync Vulnerability

MODERATE

Advisory Identifier: GHSA-j99g-7rqw-q9jg

CVSS 5.3

Published 2026-04-22

Advisory Summary

CVE-2026-34066 is a MODERATE (CVSS 5.3) peer-triggerable panic during history sync vulnerability (CWE-617: Reachable Assertion) affecting nimiq-blockchain libraries in the crates.io ecosystem. The issue involves peer-triggerable panic during history sync. Remediation is available in the latest vendor maintenance releases.

CVE-2026-34066 at a Glance

CVE Identifier CVE-2026-34066

GHSA Identifier GHSA-j99g-7rqw-q9jg

Severity MODERATE

CVSS v3.1 Base Score 5.3

CWE Classification CWE-617: Reachable Assertion

Affected Product nimiq-blockchain

Package Ecosystem crates.io

Published Date 2026-04-22

Last Updated 2026-04-27

Security Impact

CVSS: 5.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H).

Attack Vector Network (AV:N)

Attack Complexity High (AC:H)

Privileges Required None (PR:N)

User Interaction Required (UI:R)

Scope Unchanged (S:U)

Confidentiality None (C:N)

Integrity None (I:N)

Availability High (A:H)

How to Fix CVE-2026-34066

To remediate this vulnerability, upgrade all affected nimiq-blockchain dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

nimiq-blockchain fixed: Latest secure release

Upgrade nimiq-blockchain to Latest secure release

Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for nimiq-blockchain

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-34066, inspect your project dependencies for nimiq-blockchain:

inspect dependencies for nimiq-blockchain

Analyze the terminal output to locate any version of nimiq-blockchain in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than the patched release), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-617: Reachable Assertion, where the product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary. In nimiq-blockchain, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact `HistoryStore::put_historic_txns` uses an `assert!` to enforce invariants about `HistoricTransaction.block_number` (must be within the macro block being pushed and within the same epoch). During history sync, a peer can influence the `history: &[HistoricTransaction]` input passed into `Blockchain::push_history_sync`, and a malformed history list can violate these invariants and trigger a panic. `extend_history_sync` calls `this.history_store.add_to_history(..)` before comparing the computed history root against the macro block header (`block.history_root()`), so the panic can happen before later rejection checks run. ### Patches [The patch for this vulnerability](https://github.com/nimiq/core-rs-albatross/commit/6f5511309c199d84b012fe6b9aba7e5582892c50) is included as part of [v1.3.0](https://github.com/nimiq/core-rs-albatross/releases/tag/v1.3.0). ### Workarounds No known workarounds.

CVE-2026-34066 Affected nimiq-blockchain Versions

1 component(s)

Product / Package	Ecosystem	Affected Versions	Fixed Version
nimiq-blockchain	crates.io	≤ 0.2.0

References

GitHub Advisory / Wiki ADVISORY

https://github.com/nimiq/core-rs-albatross/security/advisories/GHSA-j99g-7rqw-q9jg

NVD — CVE-2026-34066 NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-34066

nimiq-blockchain Source Repository REPOSITORY

https://github.com/nimiq/core-rs-albatross/pull/3656

Security Fix Commit FIX COMMIT

https://github.com/nimiq/core-rs-albatross/commit/6f5511309c199d84b012fe6b9aba7e5582892c50

nimiq-blockchain Source Repository REPOSITORY

https://github.com/nimiq/core-rs-albatross

nimiq-blockchain Release RELEASE

https://github.com/nimiq/core-rs-albatross/releases/tag/v1.3.0

Frequently Asked Questions

What is CVE-2026-34066?

CVE-2026-34066 is a security vulnerability in nimiq-blockchain involving Peer-triggerable panic during history sync under CWE-617: Reachable Assertion.

Which nimiq-blockchain versions are affected?

Affected versions include releases prior to current release patches across affected packages: nimiq-blockchain.

What version fixes CVE-2026-34066?

Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.

Is nimiq-blockchain affected?

Yes, nimiq-blockchain is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.

What is the CVSS score of CVE-2026-34066?

CVE-2026-34066 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H.

What CWE is associated with CVE-2026-34066?

CVE-2026-34066 is classified under CWE-617: Reachable Assertion (The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.).

How can I check crates.io dependencies for CVE-2026-34066?

Run the dependency tree command: 'inspect dependencies for nimiq-blockchain'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.

Machine-readable OSV JSON OSV v1.5 Schema

Normalized schema output

View Raw JSON

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-j99g-7rqw-q9jg",
  "modified" : "2026-04-27T16:22:38Z",
  "published" : "2026-04-22T19:23:55Z",
  "aliases" : [ "CVE-2026-34066" ],
  "summary" : "nimiq-blockchain: Peer-triggerable panic during history sync",
  "details" : "### Impact\n`HistoryStore::put_historic_txns` uses an `assert!` to enforce invariants about `HistoricTransaction.block_number` (must be within the macro block being pushed and within the same epoch). During history sync, a peer can influence the `history: &[HistoricTransaction]` input passed into `Blockchain::push_history_sync`, and a malformed history list can violate these invariants and trigger a panic.\n\n`extend_history_sync` calls `this.history_store.add_to_history(..)` before comparing the computed history root against the macro block header (`block.history_root()`), so the panic can happen before later rejection checks run.\n\n### Patches\n[The patch for this vulnerability](https://github.com/nimiq/core-rs-albatross/commit/6f5511309c199d84b012fe6b9aba7e5582892c50) is included as part of [v1.3.0](https://github.com/nimiq/core-rs-albatross/releases/tag/v1.3.0).\n\n### Workarounds\nNo known workarounds.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "crates.io",
      "name" : "nimiq-blockchain"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "0.2.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/nimiq/core-rs-albatross/security/advisories/GHSA-j99g-7rqw-q9jg"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-34066"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nimiq/core-rs-albatross/pull/3656"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nimiq/core-rs-albatross/commit/6f5511309c199d84b012fe6b9aba7e5582892c50"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/nimiq/core-rs-albatross"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/nimiq/core-rs-albatross/releases/tag/v1.3.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20", "CWE-617", "CWE-754" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-22T19:23:55Z",
    "nvd_published_at" : "2026-04-22T20:16:41Z"
  }
}

CVSS V3

5.3 MODERATE