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Back to active CVEs
High · CVSS 8.7CVE-2026-123559

Zebra before 7.0.0 Denial of Service via Quadratic Sighash ComputationCVE-2026-123559

Answer in brief

CVE-2026-123559 records a High severity (CVSS 8.7) vulnerability in Zebra before 7.0.0 Denial of Service via Quadratic Sighash Computation. The current sources do not mark it as known exploited. The current feed maps ZcashFoundation/zebra (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Nov 8, 2026Updated Nov 8, 2026Source checked Nov 8, 2026First seen by HOL Nov 8, 2026Material review Nov 8, 2026
Upstream Advisory

Key facts

Risk
High · CVSS 8.7
Exploitation
Not marked as known exploited
Affected software
1 mapped package or product
Fix availability
Available

Why this deserves its current priority

CVSS is 8.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps ZcashFoundation/zebra (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
PackageAffected rangeFixed version
ZcashFoundation/zebrageneric>=0 <7.0.07.0.0

Recommended response

  1. 1Check inventory. Check lockfiles and deployed manifests for ZcashFoundation/zebra.
  2. 2Review the reported fix. Update ZcashFoundation/zebra to 7.0.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

  1. Published upstream

    Nov 8, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  2. Source modified

    Nov 8, 2026

    Evidence: source:cvelist:source_dates:source-dates:record

  3. First seen by HOL

    Nov 8, 2026

Sources and claim methodology

  • GitHub security advisorygithub.com
  • Source referencevulncheck.com
Upstream source description

Zebra before 7.0.0 contains an inefficient algorithmic complexity vulnerability that allows unauthenticated peers to exhaust verification threads by submitting transactions with many transparent inputs. Attackers can relay invalid transactions with tens of thousands of inputs, forcing quadratic ZIP-244 or ZIP-243 digest recomputation that stalls Rayon-backed block verification for minutes.

Quoted source text, attributed separately from HOL analysis.

Related CVEs

  • Hickory DNS hickory-proto 0.3.1 before 0.26.1 CPU Exhaustion via BinEncoder Name CompressionAlso CWE-407

Record context

Vulnerability class
Missing Auth
EPSS
Not reported
CWE IDs
CWE-407
Source
CVE List V5
Source checked
Nov 8, 2026
References
2 linked sources
Open source record