nessshon tonapi up to 2.2.0 Webhook Dispatcher setup path improper authorization

Summaryinfo

A vulnerability identified as critical has been detected in nessshon tonapi up to 2.2.0. Affected by this issue is the function setup of the component Webhook Dispatcher. The manipulation of the argument path leads to improper authorization. This vulnerability is referenced as CVE-2026-54635. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in nessshon tonapi up to 2.2.0 and classified as critical. This issue affects the function setup of the component Webhook Dispatcher. The manipulation of the argument path with an unknown input leads to a improper authorization vulnerability. Using CWE to declare the problem leads to CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

pytonapi is a Python SDK for TONAPI that provides REST API, streaming, and webhook access to the TON blockchain. From 2.0.0 to 2.2.0, TonapiWebhookDispatcher fails to validate the Authorization header when a webhook handler is registered with the documented path argument, because setup() stores bearer tokens only under the default suffix paths and never adds the custom path to the token map, so self._tokens.get(path) returns None and the authentication guard is skipped. An unauthenticated remote attacker can POST forged payloads to the custom webhook endpoint and trigger victim-defined handlers. This issue is fixed in version 2.2.1.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-54635 since 06/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1548.002 for this issue.

Upgrading to version 2.2.1 eliminates this vulnerability.

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Productinfo

Vendor

• nessshon

Name

• tonapi

Version

• 2.0
• 2.1
• 2.2.0

Website

• Product: https://github.com/nessshon/tonapi/

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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