CVE-2025-12559 Information Disclosure in Common Teams API

Mattermost versions 11.0.x = 11.0.2, 10.12.x = 10.12.1, 10.11.x = 10.11.4, 10.5.x = 10.5.12 fail to sanitize team email addresses to be visible only to Team Admins, which allows any authenticated user to view team email addresses via the GET /api/v4/channels/channelid/commonteams endpoint...

CVE-2025-12559 Information Disclosure in Common Teams API

Mattermost versions 11.0.x = 11.0.2, 10.12.x = 10.12.1, 10.11.x = 10.11.4, 10.5.x = 10.5.12 fail to sanitize team email addresses to be visible only to Team Admins, which allows any authenticated user to view team email addresses via the GET /api/v4/channels/channelid/commonteams endpoint...

CVE-2025-12559 Information Disclosure in Common Teams API

Mattermost versions 11.0.x = 11.0.2, 10.12.x = 10.12.1, 10.11.x = 10.11.4, 10.5.x = 10.5.12 fail to sanitize team email addresses to be visible only to Team Admins, which allows any authenticated user to view team email addresses via the GET /api/v4/channels/channelid/commonteams endpoint...

Microsoft Teams Flaw in Guest Chat Exposes Users to Malware Attacks

New research from Ontinue exposes a major security flaw in Microsoft Teams B2B Guest Access. Learn how attackers bypass all Defender for Office 365 protections with a single invite...

[SECURITY] Fedora 43 Update: gopass-1.16.0-1.fc43

The slightly more awesome standard unix password manager for teams...

GO-2025-4129 Mattermost allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL in github.com/mattermost/mattermost-server

Mattermost allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL in github.com/mattermost/mattermost-server...

Researchers Detail Tuoni C2's Role in an Attempted 2025 Real-Estate Cyber Intrusion

Cybersecurity researchers have disclosed details of a cyber attack targeting a major U.S.-based real-estate company that involved the use of a nascent command-and-control C2 and red teaming framework known as Tuoni. "The campaign leveraged the emerging Tuoni C2 framework, a relatively new,...

Bill Largent: On epic reads, lifelong learning, and empathy

Welcome to another episode of Humans of Talos! This week, Amy sits down with William Bill Largent from the Strategic Planning and Communications team. Bill's role as Senior Security Researcher spans from threat research to communicating Talos's critical work to internal teams, partners, and...

Dragon Breath Uses RONINGLOADER to Disable Security Tools and Deploy Gh0st RAT

The threat actor known as Dragon Breath has been observed making use of a multi-stage loader codenamed RONINGLOADER to deliver a modified variant of a remote access trojan called Gh0st RAT. The campaign, which is primarily aimed at Chinese-speaking users, employs trojanized NSIS installers...

CVE-2025-55073

Mattermost versions 10.11.x = 10.11.3, 10.5.x = 10.5.11, 10.12.x = 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL...

Mattermost fails to properly restrict access to archived channel search API

Mattermost versions 11 fail to properly restrict access to archived channel search API which allows guest users to discover archived public channels via the /api/v4/teams/teamid/channels/searcharchived endpoint...

GHSA-FF85-QW3H-G9VP Mattermost allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL

Mattermost versions 10.11.x = 10.11.3, 10.5.x = 10.5.11, 10.12.x = 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL...

Mattermost allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL

Mattermost versions 10.11.x = 10.11.3, 10.5.x = 10.5.11, 10.12.x = 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL...

Missing Authentication for Critical Function

Overview Affected versions of this package are vulnerable to Missing Authentication for Critical Function via the MSTeams plugin OAuth flow. An attacker can modify arbitrary posts by sending a crafted OAuth redirect URL. Remediation Upgrade...

Missing Authentication for Critical Function

Overview Affected versions of this package are vulnerable to Missing Authentication for Critical Function via the MSTeams plugin OAuth flow. An attacker can modify arbitrary posts by sending a crafted OAuth redirect URL. Remediation Upgrade...

Missing Authentication for Critical Function

Overview Affected versions of this package are vulnerable to Missing Authentication for Critical Function via the MSTeams plugin OAuth flow. An attacker can modify arbitrary posts by sending a crafted OAuth redirect URL. Remediation Upgrade github.com/mattermost/mattermost/server/channels/web to...

CVE-2025-55073

Mattermost versions 10.11.x = 10.11.3, 10.5.x = 10.5.11, 10.12.x = 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL...

CVE-2025-55073 MS Teams plugin OAuth allows editing arbitrary posts

Mattermost versions 10.11.x = 10.11.3, 10.5.x = 10.5.11, 10.12.x = 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL...

CVE-2025-55073

Mattermost Server contains CVE-2025-55073: versions 10.11.x (<=10.11.3), 10.5.x (<=10.5.11), and 10.12.x (

EUVD-2025-186555

Mattermost versions 10.11.x = 10.11.3, 10.5.x = 10.5.11, 10.12.x = 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL...