CVE-2026-46540 (GCVE-0-2026-46540)
Vulnerability from cvelistv5 – Published: 2026-06-09 23:45 – Updated: 2026-06-10 13:00
VLAI
EPSS
VEX
Title
Nimiq light-blockchain: Light blockchain rebranch issue
Summary
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.
Severity
6.5 (Medium)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-10 12:59 UTC
CWE
- CWE-841 - Improper Enforcement of Behavioral Workflow
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/nimiq/core-rs-albatross/securi… | x_refsource_CONFIRM |
| https://github.com/nimiq/core-rs-albatross/pull/3706 | x_refsource_MISC |
| https://github.com/nimiq/core-rs-albatross/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| nimiq | core-rs-albatross |
Affected:
< 1.4.0
|
guessed |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
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