CVE-2026-21535

Improper access control in Microsoft Teams allows an unauthorized attacker to disclose information over a network...

CVE-2026-21535

Improper access control in Microsoft Teams allows an unauthorized attacker to disclose information over a network...

CVE-2026-21535 Microsoft Teams Information Disclosure Vulnerability

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CVE-2026-21535

Technical details about CVE-2026-21535 are not publicly provided in the supplied documents. Monitor for updates to obtain affected products, impact details, and remediation information.

CVE-2026-21535 Microsoft Teams Information Disclosure Vulnerability

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Microsoft Teams Information Disclosure Vulnerability

Improper access control in Microsoft Teams allows an unauthorized attacker to disclose information over a network...

KLA90898 SB vulnerability in Microsoft Office

Security bypass vulnerability was found in Microsoft Teams. Malicious users can exploit this vulnerability to obtain sensitive information, bypass security restrictions. Original advisories CVE-2026-21535 Exploitation Related products Microsoft-Teams-for-Desktop CVE list CVE-2026-21535 critical...

Microsoft Teams 访问控制错误漏洞

Microsoft Teams is a software product developed by the American company Microsoft, used for online meetings, chatting, and cloud storage functions. Microsoft Teams has a vulnerability related to access control, which stems from improper access controls. This vulnerability could allow unauthorized...

PT-2026-20942

Name of the Vulnerable Software and Affected Versions Microsoft Teams affected versions not specified Description An improper access control issue exists in Microsoft Teams. This allows an unauthorized attacker to disclose sensitive information over a network. The issue is due to insufficient...

Mattermost Server 10.11.x <= 10.11.9 / 11.0.x <= 11.2.x Improper Access Control (MMSA-2025-00549)

The version of Mattermost Server installed on the remote host is affected by a vulnerability as referenced in the MMSA-2025-00549 advisory. - Mattermost versions 10.11.x = 10.11.9 and 11.0.x = 11.2.x fail to properly enforce access control checks in the common teams API. This allows the API to...

Insertion of Sensitive Information Into Sent Data

Overview openclaw is a 🦞 OpenClaw — Personal AI Assistant Affected versions of this package are vulnerable to Insertion of Sensitive Information Into Sent Data via the process that handles downloading inbound MS Teams attachments or inline images, specifically when retrying URLs with an...

OpenClaw MS Teams inbound attachment downloader leaks bearer tokens to allowlisted suffix domains

Summary NOTE: This only affects deployments that enable the optional MS Teams extension Teams channel. If you do not use MS Teams, you are not impacted. When OpenClaw downloads inbound MS Teams attachments / inline images, it may retry a URL with an Authorization: Bearer header after receiving 40...

GHSA-7VWX-582J-J332 OpenClaw MS Teams inbound attachment downloader leaks bearer tokens to allowlisted suffix domains

Summary NOTE: This only affects deployments that enable the optional MS Teams extension Teams channel. If you do not use MS Teams, you are not impacted. When OpenClaw downloads inbound MS Teams attachments / inline images, it may retry a URL with an Authorization: Bearer header after receiving 40...

CVE-2026-20796

Mattermost versions 10.11.x = 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /commonteams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549...

Time-of-check Time-of-use (TOCTOU) Race Condition

Overview Affected versions of this package are vulnerable to Time-of-check Time-of-use TOCTOU Race Condition via a race condition in the /commonteams API endpoint. An attacker can gain unauthorized access to team names by exploiting the timing of channel membership validation during data retrieva...

GHSA-2XF7-HMF6-P64J Mattermost doesn't properly validate channel membership at the time of data retrieval

Mattermost versions 10.11.x = 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /commonteams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549...

Mattermost doesn't properly validate channel membership at the time of data retrieval

Mattermost versions 10.11.x = 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /commonteams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549...

CVE-2026-20796

Mattermost versions 10.11.x = 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /commonteams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549...

CVE-2026-20796 Time-of-check time-of-use vulnerability in common teams API

Mattermost versions 10.11.x = 10.11.9 fail to properly validate channel membership at the time of data retrieval which allows a deactivated user to learn team names they should not have access to via a race condition in the /commonteams API endpoint.. Mattermost Advisory ID: MMSA-2025-00549...

CVE-2026-20796

Mattermost CVE-2026-20796 affects version 10.11.x up to 10.11.9, due to improper validation of channel membership at data retrieval. A race condition in the /common_teams API endpoint can allow a deactivated user to learn team names they should not access. Root cause: insufficient validation duri...