No-Instructions relay-server up to 0.9.6 WebSocket Endpoint authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.0$0-$5k0.00

Summaryinfo

A vulnerability was found in No-Instructions relay-server up to 0.9.6. It has been classified as critical. The impacted element is an unknown function of the component WebSocket Endpoint. This manipulation causes authorization. This vulnerability appears as CVE-2026-42889. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical was found in No-Instructions relay-server up to 0.9.6. Affected by this vulnerability is an unknown code block of the component WebSocket Endpoint. The manipulation with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-863. The 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. This allows attackers to bypass intended access restrictions. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Relay adds real-time collaboration to Obsidian. Relay Server versions 0.9.0 through 0.9.6 contain an authentication bypass in the multi-document WebSocket endpoints. When authentication is configured, WebSocket connections without a token query parameter were incorrectly treated as having full server permissions. An unauthenticated network attacker who knows or guesses a document ID could connect to the document sync WebSocket and read or modify document contents without a valid document token. This vulnerability is fixed in 0.9.7.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-42889 since 04/30/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 0.9.7 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 8.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.1
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-863 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: relay-server 0.9.7

Timelineinfo

04/30/2026 CVE reserved
05/12/2026 +12 days Advisory disclosed
05/12/2026 +0 days VulDB entry created
05/12/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-9vp9-8q9j-8mqm
Status: Confirmed

CVE: CVE-2026-42889 (🔒)
GCVE (CVE): GCVE-0-2026-42889
GCVE (VulDB): GCVE-100-363403

Entryinfo

Created: 05/12/2026 23:20
Changes: 05/12/2026 23:20 (64)
Complete: 🔍
Cache ID: 216::103

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