Vulnerability in Relay adds real-time collaboration to Obsidian. Relay Server (CVE-2026-42889)
Summary
Vulnerability in Relay adds real-time collaboration to Obsidian. Relay Server (CVE-2026-42889). Confidential information can be exposed externally. Mitigation: upgrade to 0.9.7 or later.
Original description
The description as published by the source.
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.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-42889 has been found in Relay adds real-time collaboration to Obsidian. Relay Server.
Confidential information can be exposed externally. CVSS score: 9.1/10.
What to do: upgrade Relay adds real-time collaboration to Obsidian. Relay Server to 0.9.7 or later.
If unsure, ask your IT team or search "Relay adds real-time collaboration to Obsidian. Relay Server CVE-2026-42889" on the vendor's site.
CVE-2026-42889 (Relay adds real-time collaboration to Obsidian. Relay Server) — CWE-639 / CVSS v3 9.1
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 0.9.7 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-639) exists in Relay adds real-time collaboration to Obsidian. Relay Server.
Check the vendor advisory for the affected versions of Relay adds real-time collaboration to Obsidian. Relay Server.
Severity: Critical (CVSS 9.1/10). Confidential information can be exposed externally.
Update to 0.9.7.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
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1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Relay adds real-time collaboration to Obsidian. Relay Server を使っているサービスとバージョンを洗い出す。
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2Apply patch patch
Upgrade Relay adds real-time collaboration to Obsidian. Relay Server to 0.9.7ステージング環境で 0.9.7 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
References
- advisory github.com
- advisory github.com
- advisory nvd.nist.gov