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TI-2026-67847 Aliases CVE-2026-104978

Plane project invitations can be hijacked through the join flow

Priority HIGH 71CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
High
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-863.

Summary

Plane, an open source project management tool, is affected before 1.4.0. Its project invitation list endpoint is open to any authenticated user who knows the workspace slug and project ID, and its public join endpoint accepts an invitation based only on a submitted email address (CWE-863). An attacker with a low-privilege account can enumerate a pending invitation for an email address that has not registered with Plane, register that address without mailbox verification, and accept the invitation to join the target workspace and project.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00364 30th percentileScored 2026-11-07
Fix Fixed plane (makeplane): 1.4.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
makeplaneplanebefore 1.4.01.4.0Patch availableCNA
  • plane Vendormakeplane Affected before 1.4.0 Fixed in 1.4.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:plane:plane:*:*:*:*:*:*:*:*——makeplane
  • cpe:2.3:a:plane:plane:*:*:*:*:*:*:*:* Versions — — ·makeplane

Remediation

Upgrade Plane to 1.4.0, which fixes this issue.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA plane (makeplane) Fixed in 1.4.0

Timeline

  1. 2026-10-05 Threatist record created from CVE-2026-104978
  2. 2026-10-07 Priority changed: MEDIUM → LOW
  3. 2026-10-07 CISA SSVC decision points changed
  4. 2026-10-07 Priority changed: LOW → HIGH

References

Other 4

  • TI-2026-67866 Hardcoded secret keys in Plane community deployments CVSS 3.1CRITICAL 9.8
  • TI-2026-67865 Account takeover in Plane via unverified OAuth email matching CVSS 3.1CRITICAL 9.1
  • TI-2026-67863 Plane magic-code login lacks rate limiting, allowing OTP brute force CVSS 3.1CRITICAL 9.1
  • TI-2024-32097 Plane allows server side request forgery via /_next/image endpoint CVSS 3.1CRITICAL 9.3
  • TI-2026-67862 Cross-project asset hijacking in Plane allows file takeover CVSS 3.1CRITICAL 9.6
  • TI-2026-67861 Server-side request forgery in Plane webhook delivery via redirects CVSS 3.1CRITICAL 9.9
See all 65 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences