Plane is an open-source project management tool. Prior to 1.4.0, Plane's project invitation list endpoint is accessible to any authenticated user who knows the workspace slug and project ID, while the public project invitation join endpoint accepts an invitation based only on a submitted email address. When a pending invitation targets an email address that has not registered with Plane, an attacker can enumerate the invitation, register an account using the invited email without mailbox verification, and accept the invitation. The attacker-controlled account is then added to the target workspace and project. This issue is fixed in 1.4.0.
CVE-2026-104978
HIGHPre-NVD 8.28.2
EchelonGraph scoreLOW confidence
This high-severity CVE scores 8.2 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: secondary
8.2EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: —CVSS: 8.2Exploit: None knownExposed services: Not assessed
A fix is available — apply it.
- CVSS v3
- 8.2
- EG Score
- 8.2HIGHlow confidence
- EG Risk
- 41EG Risk 41/100CISA SSVC
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity82% × 45%Exploitation0% × 40%Automatability30% × 15%CISA SSVC: Track at low or medium mission impact; Track or Attend at high (mission-essential systems).Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high. - EPSS PROB
- —
- EPSS %ILE
- —
- KEV
- Not listed
CISA SSVCTrack at low or medium mission impact; Track or Attend at high (mission-essential systems).
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation none (no KEV listing, exploit record or EPSS ≥ 50%) · Automatable unknown (not published for this CVE) · Technical impact partial (CVSS below 9.0). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table
Published
October 5, 2026
Last Modified
October 5, 2026
Advisory Details (4)
Auto-updated Oct 5, 2026🔬 Proof of concept available. Patch available. Sources: github_pr, github_commit, github_release, github.
github_release Patch Available
v1.4.0
Patch available: makeplane/plane v1.4.0
https://github.com/makeplane/plane/releases/tag/v1.4.0github_commit
commit 14a4c22f94ea (makeplane/plane)
Fix landed in makeplane/plane commit 14a4c22f94ea — awaiting tagged release
https://github.com/makeplane/plane/commit/14a4c22f94eac1582439e41112213f976c6a6cf7github_pr
[WEB-7877] fix(security): enforce token + auth validation on project invite accept/reject
Fix merged in makeplane/plane PR #9308 on 2026-07-09 — awaiting tagged release
https://github.com/makeplane/plane/pull/9308githubMentions a patch (unverified)🟡 PoC Available
Invitation Hijack in Project Join Flow via Missing Authorization and Email-Only Acceptance · Advisory · makeplane/plane · GitHub
https://github.com/makeplane/plane/security/advisories/GHSA-g36h-p63v-g9c7Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 3× in last 7d / 3× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-10-05 18:23 UTCEG score recompute
- 2026-10-05 17:56 UTCEG score recompute
- 2026-10-05 17:55 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(4)
What is CVE-2026-104978?
CVE-2026-104978 is a high vulnerability published on October 5, 2026. Plane is an open-source project management tool. Prior to 1.4.0, Plane's project invitation list endpoint is accessible to any authenticated user who knows the workspace slug and project ID, while the public project invitation join endpoint accepts an invitation based only on a submitted email…
When was CVE-2026-104978 disclosed?
CVE-2026-104978 was first published on October 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-104978?
CVE-2026-104978 has a CVSS base score of 8.2 (a secondary CVSS source that NVD displays; NVD's own analysis pending). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-104978?
A fix for CVE-2026-104978 is available: update to the fixed version the vendor names in its advisory.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-104978
Is Your Infrastructure Affected by CVE-2026-104978?
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