{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-46540", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-14T20:42:31.368Z", "datePublished": "2026-06-09T23:45:01.847Z", "dateUpdated": "2026-06-09T23:45:01.847Z"}, "containers": {"cna": {"title": "Nimiq light-blockchain: Light blockchain rebranch issue", "problemTypes": [{"descriptions": [{"cweId": "CWE-841", "lang": "en", "description": "CWE-841: Improper Enforcement of Behavioral Workflow", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L", "version": "3.1"}}], "references": [{"name": "https://github.com/nimiq/core-rs-albatross/security/advisories/GHSA-m3pg-qc2q-mg8c", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/nimiq/core-rs-albatross/security/advisories/GHSA-m3pg-qc2q-mg8c"}, {"name": "https://github.com/nimiq/core-rs-albatross/pull/3706", "tags": ["x_refsource_MISC"], "url": "https://github.com/nimiq/core-rs-albatross/pull/3706"}, {"name": "https://github.com/nimiq/core-rs-albatross/releases/tag/v1.4.0", "tags": ["x_refsource_MISC"], "url": "https://github.com/nimiq/core-rs-albatross/releases/tag/v1.4.0"}], "affected": [{"vendor": "nimiq", "product": "core-rs-albatross", "versions": [{"version": "< 1.4.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-06-09T23:45:01.847Z"}, "descriptions": [{"lang": "en", "value": "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."}], "source": {"advisory": "GHSA-m3pg-qc2q-mg8c", "discovery": "UNKNOWN"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "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."}], "id": "CVE-2026-46540", "lastModified": "2026-06-10T00:16:54.230", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 2.5, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-06-10T00:16:54.230", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/nimiq/core-rs-albatross/pull/3706"}, {"source": "security-advisories@github.com", "url": "https://github.com/nimiq/core-rs-albatross/releases/tag/v1.4.0"}, {"source": "security-advisories@github.com", "url": "https://github.com/nimiq/core-rs-albatross/security/advisories/GHSA-m3pg-qc2q-mg8c"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-841"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.4.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "core-rs-albatross", "source": "cna", "vendor": "nimiq"}, "product": "core-rs-albatross", "vendor": "nimiq"}], "created": "2026-06-10T02:15:19.175783+00:00", "updated": "2026-06-10T02:45:15.713087+00:00", "vendors": ["nimiq", "nimiq$PRODUCT$core-rs-albatross"]}