CVE-2026-123555

Description

Zebra from 2.3.0 before 7.0.0 contains a denial of service vulnerability that allows unauthenticated peers to evade misbehavior scoring by sending transactions or blocks with invalid transparent scripts. Attackers can flood mempool with script-failing transactions or serve forged v5 block bodies with altered scriptSig bytes to exhaust CPU and repeatedly stall block sync.

Overview

State: PUBLISHED
Assigner (CNA): VulnCheck
CVSS severity: HIGH
CVSS score: 8.7 / 10
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Effective score: 8.7 / 10 HIGH source: CNA overview
CWE(s): CWE-755
Reserved: 2026-11-06
Published: 2026-11-08 01:37 UTC
Last updated: 2026-11-08 01:37 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/123xxx/CVE-2026-123555.json
Linked Threat: CVE-2026-123555 — Zebra 2.3.0 before 7.0.0 Denial of Service via Unscored Script Verification Failures

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-119440

EUVD enrichment is queued; refresh the page in a few seconds.

Affected products (2)

Vendor	Product	Versions	Platforms
ZcashFoundation	zebra	`2.3.0` (affected), `7.0.0` (unaffected)	—
ZcashFoundation	zebra	`1.0.0-beta.46` (affected), `18.0.0` (unaffected)	—

Vendor references (3)

References embedded in the original CVE record by the assigning CNA.

GitHub Security Advisory (GHSA-jq45-ghw5-v37x) vendor-advisory
Patch Commit patch
VulnCheck Advisory: Zebra 2.3.0 before 7.0.0 Denial of Service via Unscored Script Verification Failures third-party-advisory

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

Remediations (10)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

September 2026 Critical Security Patch Update Released

web:blogs.oracle.com

For more information about the Critical Security Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.

2026-11-08 10:24 UTC
CVE Database Search & Remediation Guidance

web:cvedatabase.com

Search and analyze CVE vulnerabilities with instant access to CVSS scores, affected products, and remediation guidance.

2026-11-08 10:24 UTC
CISA Requires Federal Agencies to Patch Critical Vulnerabilities Within ...

web:cybersecuritynews.com

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has issued Binding Operational Directive (BOD) 26-04, titled "Prioritizing Security Updates Based on Risk," compelling all Federal Civilian Executive Branch (FCEB) agencies to remediate the most dangerous known exploited vulnerabilities within just three calendar days.

2026-11-08 10:24 UTC
CVE Vulnerabilities 2026: Critical Flaws & Fixes Hub

web:cyberupdates365.com

Track critical CVE vulnerabilities 2026 with verified enterprise patch guides. Fix zero-days across VMware, WordPress, Windows, and cloud infrastructure.

2026-11-08 10:24 UTC
Microsoft Patch Tracker (November 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-11-08 10:24 UTC
What Is CVE Remediation in 2026? - aikido.dev

web:www.aikido.dev

CVE remediation is fixing known flaws in the software you run. Why upgrading often fails, what remediation actually involves, and how backporting fixes it.

2026-11-08 10:24 UTC
Microsoft October 2026 Patch Tuesday fixes 1,411 flaws, 3 zero-days

web:www.bleepingcomputer.com

Today is Microsoft's October 2026 Patch Tuesday, with security updates addressing a record-breaking 1,411 flaws, including one actively exploited and two publicly disclosed zero-day vulnerabilities.

2026-11-08 10:24 UTC
The 8 Best Automated Vulnerability Remediation Tools in 2026

web:www.openhands.dev

Compare 8 automated vulnerability remediation tools for 2026 on fixes, prioritization, integrations, and deployment control.

2026-11-08 10:24 UTC
Oracle Critical Patch Update Advisory - October 2026

web:www.oracle.com

This Critical Patch Update contains 1295 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at October 2026 Critical Patch Update: Executive Summary and Analysis.

2026-11-08 10:24 UTC
Oracle Critical Security Patch Update Advisory - September 2026

web:www.oracle.com

Prior Critical Patch Update and Critical Security Patch Update advisories should be reviewed for information regarding earlier published security patches. Refer to Critical Patch Updates, Critical Security Patch Updates, Security Alerts and Bulletins for information about Oracle Security advisories.

2026-11-08 10:24 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-123555.json.

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:cargo/zebrad",
          "product": "zebra",
          "vendor": "ZcashFoundation",
          "versions": [
            {
              "lessThan": "7.0.0",
              "status": "affected",
              "version": "2.3.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "7.0.0",
              "versionType": "semver"
            }
          ]
        },
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:cargo/zebra-consensus",
          "product": "zebra",
          "vendor": "ZcashFoundation",
          "versions": [
            {
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              "status": "affected",
              "version": "1.0.0-beta.46",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "18.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:zfnd:zebra:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0.0",
                  "versionStartIncluding": "2.3.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:zfnd:zebra:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "18.0.0",
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                }
              ],
              "negate": false,
              "operator": "OR"
            }
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      "credits": [
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      ],
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        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
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            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
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            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
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            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
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      ],
      "problemTypes": [
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      "providerMetadata": {
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      },
      "references": [
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          "tags": [
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          ],
          "url": "https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-jq45-ghw5-v37x"
        },
        {
          "name": "Patch Commit",
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          ],
          "url": "https://github.com/ZcashFoundation/zebra/commit/e8db87eb69254e0d4eedd058eadd48bdfa09065a"
        },
        {
          "name": "VulnCheck Advisory: Zebra 2.3.0 before 7.0.0 Denial of Service via Unscored Script Verification Failures",
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          ],
          "url": "https://www.vulncheck.com/advisories/zebra-2.3.0-before-7.0.0-denial-of-service-via-unscored-script-verification-failures"
        }
      ],
      "title": "Zebra 2.3.0 before 7.0.0 Denial of Service via Unscored Script Verification Failures",
      "x_generator": {
        "engine": "vulncheck-endgame"
      }
    }
  },
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    "datePublished": "2026-11-08T01:37:57.593Z",
    "dateReserved": "2026-11-06T00:50:45.482Z",
    "dateUpdated": "2026-11-08T01:37:57.593Z",
    "state": "PUBLISHED"
  },
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}