Skip to main content
EPSS 0.4%top 65%

CVE-2026-54635: CWE-287: Improper Authentication in nessshon tonapi

0
High
Published: 07/28/2026 (07/28/2026, 17:09:08 UTC)
Source: CVE Database V5
Vendor/Project: nessshon
Product: tonapi

Description

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.

CVSS v3.1

Score 7.5high

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected software

nessshon

tonapi

Affected versions
>=2.0.0 <2.2.1

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 08/12/2026, 13:18:51 UTC

Technical Analysis

The vulnerability exists because the TonapiWebhookDispatcher stores bearer tokens only under default suffix paths and does not add custom webhook paths to the token map. Consequently, when a webhook handler is registered with a custom path, the authentication check is skipped as self._tokens.get(path) returns None. This allows unauthenticated remote attackers to POST forged payloads to custom webhook endpoints and execute victim-defined webhook handlers. The flaw is present in pytonapi versions from 2.0.0 up to but not including 2.2.1 and is resolved in version 2.2.1.

Potential Impact

An unauthenticated remote attacker can bypass authentication controls on custom webhook endpoints, allowing them to send arbitrary payloads that trigger webhook handlers defined by the victim. This can lead to unauthorized actions being performed via the webhook handlers, impacting the integrity of the system. There is no direct confidentiality or availability impact reported.

Mitigation Recommendations

Upgrade pytonapi to version 2.2.1 or later, where this authentication bypass vulnerability is fixed. No other mitigations are specified or necessary once the update is applied.

Pro Console: star threats, build custom feeds, automate alerts via Slack, email & webhooks.Upgrade to Pro

Technical Details

Data Version
5.2
Assigner Short Name
GitHub_M
Date Reserved
2026-06-15T20:07:02.185Z
Cvss Version
3.1
State
PUBLISHED

Threat ID: 6a68e55f9c2644c7f8f2481b

Added to database: 07/28/2026, 17:22:39 UTC

Last enriched: 08/12/2026, 13:18:51 UTC

Last updated: 09/11/2026, 07:31:54 UTC

Views: 85

Community Reviews

0 reviews

Crowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.

Sort by
Loading community insights…

Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.

Actions

PRO

Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.

Please log in to the Console to use AI analysis features.

Need more coverage?

Upgrade to Pro Console for AI refresh and higher limits.

For incident response and remediation, OffSeq services can help resolve threats faster.

Latest Threats

Breach by OffSeqOFFSEQFRIENDS — 25% OFF

Check if your credentials are on the dark web

Instant breach scanning across billions of leaked records. Free tier available.

Scan now
OffSeq TrainingCredly Certified

Lead Pen Test Professional

Technical5-day eLearningPECB Accredited
View courses