CVE-2026-46540

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 82% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 6.5Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Nimiq is a Rust implementation of the Nimiq Proof-of-Stake protocol based on the Albatross consensus algorithm. Prior to version 1.4.0, when LightBlockchain::rebranch() adopts a fork chain whose tip is a macro block (checkpoint or election), it only updates self.head but fails to update self.macro_head, self.election_head, self.current_validators, or store the election header in the chain_store. This is in direct contrast with the full Blockchain::rebranch() at blockchain/src/blockchain/push.rs:504-518, which correctly updates all macro/election state when the new head is a macro block. After a rebranch to a macro block, the stale macro_head causes subsequent macro blocks pushed via push() to be verified against the wrong predecessor via verify_macro_successor(&this.macro_head). If the rebranch target was an election block, the stale current_validators causes every subsequent block to fail verify_validators(), completely stalling the light client's chain progression. This issue has been patched in version 1.4.0.

CVSS v3
6.5
EG Score
6.5MEDIUMmedium confidence
EG Risk
34
EG Risk 34/100

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity65% × 45%
Exploitation0% × 40%
Automatability30% × 15%
EPSS PROB
0.4%
EPSS %ILE
37th
KEV
Not listed

Published

June 10, 2026

Last Modified

July 23, 2026

Advisory Details (3)

Auto-updated Jun 13, 2026
Patch available. Sources: github_pr, github_release, github.
githubMentions a patch (unverified)

Light blockchain rebranch issue · Advisory · nimiq/core-rs-albatross · GitHub

https://github.com/nimiq/core-rs-albatross/security/advisories/GHSA-m3pg-qc2q-mg8c
github_release Patch Available

Mainnet 1.4.0

Patch available: nimiq/core-rs-albatross v1.4.0

https://github.com/nimiq/core-rs-albatross/releases/tag/v1.4.0
github_pr Patch Available

Fixes rebranch logic in light blockchain

Patch available: nimiq/core-rs-albatross v1.4.0 (PR #3706 merged 2026-04-22)

https://github.com/nimiq/core-rs-albatross/pull/3706

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 26× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 148 total refreshes for this CVE.

  1. 2026-10-09 20:07 UTCEPSS rescore
  2. 2026-10-08 17:12 UTCEPSS rescore
  3. 2026-10-07 23:48 UTCEPSS rescore
  4. 2026-10-06 15:18 UTCEPSS rescore
  5. 2026-10-05 17:43 UTCEPSS rescore
  6. 2026-10-04 23:22 UTCEPSS rescore
  7. 2026-10-03 14:25 UTCEPSS rescore
  8. 2026-10-03 09:39 UTCOSV refresh
  9. 2026-10-01 19:50 UTCEPSS rescore
  10. 2026-09-30 15:03 UTCEPSS rescore
  11. 2026-09-28 13:51 UTCEPSS rescore
  12. 2026-09-27 13:48 UTCEPSS rescore
  13. 2026-09-26 15:59 UTCEPSS rescore
  14. 2026-09-26 00:27 UTCEPSS rescore
  15. 2026-09-23 17:53 UTCEPSS rescore
  16. 2026-09-20 20:15 UTCEPSS rescore
  17. 2026-09-18 19:28 UTCEPSS rescore
  18. 2026-09-17 19:31 UTCEPSS rescore
  19. 2026-09-16 14:08 UTCEPSS rescore
  20. 2026-09-16 05:15 UTCEPSS rescore
  21. 2026-09-14 04:20 UTCEG score recompute
  22. 2026-09-13 16:47 UTCEPSS rescore
  23. 2026-09-12 15:01 UTCEPSS rescore
  24. 2026-09-11 14:53 UTCEPSS rescore
  25. 2026-09-11 09:37 UTCEPSS rescore
Show 75 more
  1. 2026-09-10 09:34 UTCEPSS rescore
  2. 2026-09-08 22:00 UTCEPSS rescore
  3. 2026-09-07 16:01 UTCEPSS rescore
  4. 2026-09-06 13:47 UTCEPSS rescore
  5. 2026-09-04 05:06 UTCEPSS rescore
  6. 2026-09-02 14:12 UTCEPSS rescore
  7. 2026-09-01 13:54 UTCEPSS rescore
  8. 2026-08-31 00:23 UTCEG score recompute
  9. 2026-08-30 19:17 UTCEPSS rescore
  10. 2026-08-30 01:22 UTCEPSS rescore
  11. 2026-08-28 21:41 UTCEPSS rescore
  12. 2026-08-27 14:25 UTCEPSS rescore
  13. 2026-08-26 14:46 UTCEPSS rescore
  14. 2026-08-25 13:49 UTCEPSS rescore
  15. 2026-08-25 00:30 UTCEG score recompute
  16. 2026-08-23 10:58 UTCEG score recompute
  17. 2026-08-23 00:19 UTCEPSS rescore
  18. 2026-08-21 23:49 UTCEPSS rescore
  19. 2026-08-21 19:40 UTCEG score recompute
  20. 2026-08-20 22:55 UTCEPSS rescore
  21. 2026-08-20 17:24 UTCEG score recompute
  22. 2026-08-19 17:04 UTCEPSS rescore
  23. 2026-08-19 15:39 UTCEG score recompute
  24. 2026-08-18 13:48 UTCEPSS rescore
  25. 2026-08-17 13:47 UTCEPSS rescore
  26. 2026-08-17 13:45 UTCEG score recompute
  27. 2026-08-16 14:56 UTCEPSS rescore
  28. 2026-08-16 12:25 UTCEG score recompute
  29. 2026-08-16 02:14 UTCEPSS rescore
  30. 2026-08-15 11:06 UTCEG score recompute
  31. 2026-08-15 01:30 UTCEPSS rescore
  32. 2026-08-14 06:56 UTCEG score recompute
  33. 2026-08-13 22:00 UTCEPSS rescore
  34. 2026-08-13 05:37 UTCEG score recompute
  35. 2026-08-12 13:51 UTCEPSS rescore
  36. 2026-08-12 04:05 UTCEG score recompute
  37. 2026-08-11 02:45 UTCEG score recompute
  38. 2026-08-11 00:00 UTCEPSS rescore
  39. 2026-08-10 01:24 UTCEG score recompute
  40. 2026-08-09 13:46 UTCEPSS rescore
  41. 2026-08-09 00:05 UTCEG score recompute
  42. 2026-08-08 16:37 UTCEPSS rescore
  43. 2026-08-07 22:45 UTCEG score recompute
  44. 2026-08-06 21:25 UTCEG score recompute
  45. 2026-08-06 13:47 UTCEPSS rescore
  46. 2026-08-05 20:05 UTCEG score recompute
  47. 2026-08-05 19:17 UTCEPSS rescore
  48. 2026-08-04 16:14 UTCEG score recompute
  49. 2026-08-04 15:10 UTCEPSS rescore
  50. 2026-08-04 10:39 UTCEPSS rescore
  51. 2026-08-03 14:54 UTCEG score recompute
  52. 2026-08-03 10:36 UTCEPSS rescore
  53. 2026-08-02 11:10 UTCEG score recompute
  54. 2026-08-02 02:27 UTCEPSS rescore
  55. 2026-08-01 09:49 UTCEG score recompute
  56. 2026-08-01 04:16 UTCEPSS rescore
  57. 2026-07-31 00:49 UTCEG score recompute
  58. 2026-07-30 16:28 UTCEPSS rescore
  59. 2026-07-30 01:30 UTCEPSS rescore
  60. 2026-07-29 10:54 UTCEG score recompute
  61. 2026-07-28 15:36 UTCEPSS rescore
  62. 2026-07-28 09:33 UTCEG score recompute
  63. 2026-07-27 14:13 UTCEPSS rescore
  64. 2026-07-27 08:09 UTCEG score recompute
  65. 2026-07-26 14:54 UTCEPSS rescore
  66. 2026-07-26 14:54 UTCEPSS rescore
  67. 2026-07-26 05:26 UTCEG score recompute
  68. 2026-07-25 14:18 UTCEPSS rescore
  69. 2026-07-24 14:17 UTCEPSS rescore
  70. 2026-07-23 14:18 UTCEPSS rescore
  71. 2026-07-23 03:17 UTCEG score recompute
  72. 2026-07-22 14:08 UTCEPSS rescore
  73. 2026-07-21 15:24 UTCEPSS rescore
  74. 2026-07-20 17:08 UTCEPSS rescore
  75. 2026-07-19 14:31 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-46540?
CVE-2026-46540 is a medium vulnerability published on June 10, 2026. Nimiq is a Rust implementation of the Nimiq Proof-of-Stake protocol based on the Albatross consensus algorithm. Prior to version 1.4.0, when LightBlockchain::rebranch() adopts a fork chain whose tip is a macro block (checkpoint or election), it only updates self.head but fails to update…
When was CVE-2026-46540 disclosed?
CVE-2026-46540 was first published on June 10, 2026, with the most recent update on July 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-46540 actively exploited?
CVE-2026-46540 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (37th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-46540?
CVE-2026-46540 has a CVSS base score of 6.5 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-46540?
A fix for CVE-2026-46540 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-46540

Explore →

Is Your Infrastructure Affected by CVE-2026-46540?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.