CVE-2026-82406

Description

Klever-Go is the Go implementation of the Klever blockchain protocol. Prior to 1.7.20, the native marketplace function core/kapp/market/market.go Buy does not check IsClaimed before accepting a bid. A seller can use the Claim seller-accept branch to settle a resting-bid auction while leaving the claimed order loadable with a future EndTime and stale CurrentBid and CurrentBidder values. A later bidder can submit a higher bid, be debited, and cause the previous bidder to receive a refund even though the NFT has already been delivered. Because Claim and CancelOrder reject the later bidder when IsClaimed is true, the later bidder cannot obtain the NFT or recover the funds. This issue is fixed in version 1.7.20.

Overview

State: PUBLISHED
Assigner (CNA): GitHub_M
CVSS severity: HIGH
CVSS score: 7.1 / 10
CVSS vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Effective score: 7.1 / 10 HIGH source: CNA overview
CWE(s): CWE-841
Reserved: 2026-08-28
Published: 2026-09-23 19:10 UTC
Last updated: 2026-09-23 19:10 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/82xxx/CVE-2026-82406.json
Linked Threat: CVE-2026-82406 — Klever-Go: Zombie-order theft: `Buy` missing `IsClaimed` guard in native marketplace

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-09-23 20:17:16 UTC
NVD last modified: 2026-09-23 20:17:16 UTC

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-2026-85573

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

Affected products (1)

Vendor	Product	Versions	Platforms
klever-io	klever-go	`< 1.7.20` (affected)	—

Vendor references (4)

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

https://github.com/klever-io/klever-go/security/advisories/GHSA-26r5-4mm2-px5c x_refsource_CONFIRM
https://github.com/klever-io/klever-go/pull/16 x_refsource_MISC
https://github.com/klever-io/klever-go/commit/063bb3ed98f9a84a4b1f7286680613a5fc3c91b2 x_refsource_MISC
https://github.com/klever-io/klever-go/releases/tag/v1.7.20 x_refsource_MISC

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.

NVD-tagged references (4)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://github.com/klever-io/klever-go/commit/063bb3ed98f9a84a4b1f7286680613a5fc3c91b2 security-advisories@github.com
https://github.com/klever-io/klever-go/pull/16 security-advisories@github.com
https://github.com/klever-io/klever-go/releases/tag/v1.7.20 security-advisories@github.com
https://github.com/klever-io/klever-go/security/advisories/GHSA-26r5-4mm2-px5c security-advisories@github.com

Remediations (10)

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

Microsoft Defender Patch Bypass: High Severity Zero-Day Privilege ...

web:arcticwolf.com

Validate Group Policy and registry settings for Defender to ensure real-time protection, automatic remediation , and exclusion policies are secured. Temporary Workarounds Block Vulnerable Apps: Use Microsoft Defender Vulnerability Management to block or warn against execution of affected binaries for systems pending a patch .

2026-09-24 11:11 UTC
Blackpoint Cyber Threat Notice: September 2026 Patch Tuesday Updates

web:blackpointcyber.com

Microsoft's September 2026 Patch Tuesday addressed more than 950 vulnerabilities, its largest release to date, including two elevation-of-privilege zero-days confirmed as exploited in the wild.

2026-09-24 11:11 UTC
CVE-2026-82406: Klever Go Vulnerability (CVSS 7.1) | CVETodo

web:cvetodo.com

CVE-2026-82406 is a CVSS 7.1 high-severity vulnerability in Klever Go. Includes technical details, affected versions, and mitigation steps.

2026-09-24 11:11 UTC
Microsoft Patch Tracker (September 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.

2026-09-24 11:11 UTC
Microsoft Patch Tuesday, August 2026: Updates, CVEs, and Exploited Bugs ...

web:senserva.com

The August 2026 Microsoft Patch Tuesday release (August 11, 2026 ): 67 updates fixing 751 CVEs , 4 actively exploited (CISA KEV). Ranked by real-world risk, free.

2026-09-24 11:11 UTC
Description of the security update for Office 2016: August 11, 2026 ...

web:support.microsoft.com

Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?) How to get and install the update Method 1: Microsoft Update This update is available from Microsoft Update. When you turn on ...

2026-09-24 11:11 UTC
Microsoft August 2026 Patch Tuesday fixes 400 flaws, 3 zero-days

web:www.bleepingcomputer.com

Today is Microsoft's August 2026 Patch Tuesday, and with it comes security updates for a massive 400 flaws, including one actively exploited and two publicly disclosed zero-day vulnerabilities.

2026-09-24 11:11 UTC
Critical Patches Issued for Microsoft Products, August 11, 2026

web:www.cisecurity.org

<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...

2026-09-24 11:11 UTC
CVE-2026-82406: klever-io klever-go: Klever-Go is the Go ... - Rapid7

web:www.rapid7.com

CVE-2026-82406 : klever-io klever-go: Klever-Go is the Go implementation of the Klever blockchain protocol. View severity, references, and remediation details from Rapid7.

2026-09-24 11:11 UTC
CISA KEV September 16, 2026: Three CVE Patch Analysis

web:www.secpod.com

Patch Timeline & Exploitation Gap Analysis The September 16, 2026 dataset contains three CISA KEV vulnerabilities. Each record was added to the catalog on September 16, 2026 and assigned a remediation deadline of September 19, 2026 . Consequently, all three vulnerabilities have an identical three-calendar-day KEV inclusion-to- remediation window.

2026-09-24 11:11 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-82406.json.

{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "klever-go",
          "vendor": "klever-io",
          "versions": [
            {
              "status": "affected",
              "version": "< 1.7.20"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Klever-Go is the Go implementation of the Klever blockchain protocol. Prior to 1.7.20, the native marketplace function core/kapp/market/market.go Buy does not check IsClaimed before accepting a bid. A seller can use the Claim seller-accept branch to settle a resting-bid auction while leaving the claimed order loadable with a future EndTime and stale CurrentBid and CurrentBidder values. A later bidder can submit a higher bid, be debited, and cause the previous bidder to receive a refund even though the NFT has already been delivered. Because Claim and CancelOrder reject the later bidder when IsClaimed is true, the later bidder cannot obtain the NFT or recover the funds. This issue is fixed in version 1.7.20."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 7.1,
            "baseSeverity": "HIGH",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-841",
              "description": "CWE-841: Improper Enforcement of Behavioral Workflow",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-23T19:10:23.367Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/klever-io/klever-go/security/advisories/GHSA-26r5-4mm2-px5c",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/klever-io/klever-go/security/advisories/GHSA-26r5-4mm2-px5c"
        },
        {
          "name": "https://github.com/klever-io/klever-go/pull/16",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/klever-io/klever-go/pull/16"
        },
        {
          "name": "https://github.com/klever-io/klever-go/commit/063bb3ed98f9a84a4b1f7286680613a5fc3c91b2",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/klever-io/klever-go/commit/063bb3ed98f9a84a4b1f7286680613a5fc3c91b2"
        },
        {
          "name": "https://github.com/klever-io/klever-go/releases/tag/v1.7.20",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/klever-io/klever-go/releases/tag/v1.7.20"
        }
      ],
      "source": {
        "advisory": "GHSA-26r5-4mm2-px5c",
        "discovery": "UNKNOWN"
      },
      "title": "Klever-Go: Zombie-order theft: `Buy` missing `IsClaimed` guard in native marketplace"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-82406",
    "datePublished": "2026-09-23T19:10:23.367Z",
    "dateReserved": "2026-08-28T22:00:43.513Z",
    "dateUpdated": "2026-09-23T19:10:23.367Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}