CVE-2026-3473 (GCVE-0-2026-3473)
Vulnerability from cvelistv5
Published
2026-05-22 10:27
Modified
2026-05-22 12:12
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-639 - Authorization Bypass Through User-Controlled Key
Summary
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate file ownership and access control, which allows an authenticated user to access and download files belonging to other users or teams via crafted Boards API requests using valid file IDs.. Mattermost Advisory ID: MMSA-2026-00620
References
| URL | Tags | ||||
|---|---|---|---|---|---|
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Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Mattermost | Mattermost |
Version: 11.6.0 ≤ 11.6.0 Version: 11.5.0 ≤ 11.5.3 Version: 11.4.0 ≤ 11.4.4 Version: 10.11.0 ≤ 10.11.14 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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