Cyber Resilience

CVE-2025-47870

Access Control in Mattermost Server 9.11.0 – 9.11.18

Published
21 August 2025
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 4.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
EPSS Score 0.0022 12th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2025-47870 is a medium-severity Missing Authentication for Critical Function (CWE-306) vulnerability in Mattermost Mattermost Server. Its CVSS base score is 4.3 (Medium).

Operationally, ranked at the 12th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-6 (Least Privilege) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.9.x <= 10.9.2 fail to sanitize the team invite ID in the POST /api/v4/teams/:teamId/restore endpoint which allows an team admin with no member invite privileges to get the team’s…

more

invite id.

CWE(s)

Related Threats

CVEs Like This One

CVE-2025-6226Same product: Mattermost Mattermost Server
CVE-2025-55073Same product: Mattermost Mattermost Server
CVE-2025-25068Same product: Mattermost Mattermost Server
CVE-2025-13870Same product: Mattermost Mattermost Server
CVE-2026-6673Same product: Mattermost Mattermost Server
CVE-2025-55070Same product: Mattermost Mattermost Server
CVE-2025-27538Same product: Mattermost Mattermost Server
CVE-2024-2450Same product: Mattermost Mattermost Server
CVE-2026-6343Same product: Mattermost Mattermost Server
CVE-2026-2462Same product: Mattermost Mattermost Server

Affected Assets

mattermost
mattermost server
9.11.0 — 9.11.18 · 10.5.0 — 10.5.9 · 10.8.0 — 10.8.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • AC-6 Least Privilege
  • AC-24 Access Control Decisions
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.2.3
  • V6.4.4
  • V10.4.16
  • V12.1.3

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces authorization checks so that only principals possessing the member-invite privilege can obtain a team invite ID via the /restore endpoint.

prevent

Ensures a team admin account is granted only the privileges explicitly required for its role and never receives the invite-ID retrieval permission.

prevent

Requires the system to base the decision to return the invite ID on an explicit access-control decision rather than on team-admin role membership alone.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-03 full match
prevents

Directly requires authentication of users/services/hardware, which eliminates missing authentication for critical functions.

PR.AA-01 partial match
prevents

Managing identities and credentials is a prerequisite for authentication but does not itself enforce it on critical functions.

PR.AA-05 partial match
prevents

Defining and enforcing authorizations assumes prior authentication and therefore only partially mitigates the absence of authentication.

PR.IR-01 partial match
prevents

Protecting networks from unauthorized access can be undermined by missing authentication but does not address the root authentication gap.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

The control explicitly calls for authentication before any critical function is reached, eliminating the possibility of bypassing authentication for high-value operations.

prevents

Mandating authentication requirements for critical functions at the requirements-gathering stage ensures that essential operations are not left unprotected by missing login or verification mechanisms.

mitigates

Mandating authentication for network services and critical functions stops attackers from invoking sensitive operations without credentials, closing gaps where authentication is absent for important capabilities.

prevents

Security engineering principles insist on authentication and authorization for every critical function, eliminating entry points that lack any access control mechanism.

none

Requiring strong authentication and access-privilege enablement for remote connections ensures that critical functions cannot be invoked without proper verification, closing a gap that would otherwise allow unauthenticated use.

none

Mandatory use of access cards, biometrics, or two-factor authentication ensures that critical physical areas cannot be entered without proper authentication.

References