CVE-2026-82406 (GCVE-0-2026-82406)

Vulnerability from cvelistv5 – Published: 2026-09-23 19:10 – Updated: 2026-09-24 15:20
VLAI
Title
Klever-Go: Zombie-order theft: `Buy` missing `IsClaimed` guard in native marketplace
Summary
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.
Severity
7.1 (High)
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
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-24 15:20 UTC
CWE
  • CWE-841 - Improper Enforcement of Behavioral Workflow
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7798 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
klever-io klever-go Affected: < 1.7.20
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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