Authentication Bypass in Plane (CVE-2026-105640)
Summary
Authentication bypass in Plane (CVE-2026-105640). Confidential information can be exposed externally. Mitigation: upgrade to 1.4.0 or later.
Original description
The description as published by the source.
Plane is an open-source project management tool. Prior to 1.4.0, Plane trusts email addresses returned by Gitea OAuth and by self-managed GitLab OAuth deployments where email confirmation is disabled, without verifying that the provider authenticated ownership of the address. An attacker can set an OAuth identity's unverified provider email to a victim's address, which Plane matches directly to the victim's existing local account. The attacker can then log in to the victim's Plane account without knowing the victim's password. GitHub, GitLab.com, and Google are not affected because those providers return verified email addresses. This issue is fixed in 1.4.0.
Source: NIST National Vulnerability Database NVD
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-2026-105640 has been found in Plane.
Confidential information can be exposed externally. CVSS score: 9.1/10.
What to do: upgrade Plane to 1.4.0 or later.
If unsure, ask your IT team or search "Plane CVE-2026-105640" on the vendor's site.
CVE-2026-105640 (Plane) — CWE-287 / CVSS v3 9.1
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Patched: 1.4.0 — 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.
Authentication bypass (CWE-287) exists in Plane.
Check the vendor advisory for the affected versions of Plane.
Severity: Critical (CVSS 9.1/10). Confidential information can be exposed externally.
Update to 1.4.0.
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. Run grep -r 'Plane' . against your dependency files (package-lock.json, requirements.txt, go.sum) 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
grep -r 'Plane' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Planeを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade Plane to 1.4.0ステージング環境で 1.4.0 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。