CVE-2026-33471

{"id": "CVE-2026-33471", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "CHANGED", "version": "3.1", "baseScore": 9.6, "attackVector": "NETWORK", "baseSeverity": "CRITICAL", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 5.8, "exploitabilityScore": 3.1}]}, "published": "2026-04-22T20:16:40.317", "references": [{"url": "https://github.com/nimiq/core-rs-albatross/commit/d02059053181ed8ddad6b59a0adfd661ef5cd823", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/nimiq/core-rs-albatross/releases/tag/v1.3.0", "tags": ["Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/nimiq/core-rs-albatross/security/advisories/GHSA-6973-8887-87ff", "tags": ["Patch", "Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-20"}, {"lang": "en", "value": "CWE-190"}, {"lang": "en", "value": "CWE-345"}, {"lang": "en", "value": "CWE-1284"}]}], "descriptions": [{"lang": "en", "value": "nimiq-block contains block primitives to be used in Nimiq's Rust implementation. `SkipBlockProof::verify` computes its quorum check using `BitSet.len()`, then iterates `BitSet` indices and casts each `usize` index to `u16` (`slot as u16`) for slot lookup. Prior to version 1.3.0, if an attacker can get a `SkipBlockProof` verified where `MultiSignature.signers` contains out-of-range indices spaced by 65536, these indices inflate `len()` but collide onto the same in-range `u16` slot during aggregation. This makes it possible for a malicious validator with far fewer than `2f+1` real signer slots to pass skip block proof verification by multiplying a single BLS signature by the same factor. The patch for this vulnerability is included as part of v1.3.0. No known workarounds are available."}], "lastModified": "2026-04-24T17:11:40.037", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:nimiq:nimiq_proof-of-stake:*:*:*:*:*:rust:*:*", "vulnerable": true, "matchCriteriaId": "CD0CAAD1-7626-4A4A-A6F8-9DC46FE50731", "versionEndExcluding": "1.3.0"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}