CVE-2026-82405: klever-io klever-go Incorrect Authorization

Vulnerability summary

CVE-2026-82405 is a high (CVSS 8.7) Incorrect Authorization vulnerability in klever-io klever-go. EPSS estimates a 0.26% chance of exploitation in the next 30 days, higher than 16.7% of scored vulnerabilities.

Timeline

1. 23-09-2026
   PublishedVulnerability first disclosed.
2. 24-09-2026
   Last modifiedVulnerability information updated.

Description

Klever-Go is the Go implementation of the Klever blockchain protocol. Prior to 1.7.20, the KleverUpdateAccountPermission built-in authorizes replacement of a target account's permissions by checking attacker-controlled vmInput.RecipientAddr instead of authenticated vmInput.CallerAddr. An attacker-controlled contract can choose a victim account with configured permissions as RecipientAddr, and contractHasValidPermission can accept the victim's default self-signer as authorization. UpdatePermission can then replace the victim's entire permission set with attacker-supplied Owner permissions, enabling asset theft or permanent lockout without a victim key or signature. Accounts without stored permissions and the native transaction path are not affected. This issue is fixed in version 1.7.20.

• CWE-863Incorrect AuthorizationThe product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.