CVE-2026-27656

Mattermost versions 11.4.x = 11.4.0, 11.3.x = 11.3.1, 11.2.x = 11.2.3, 10.11.x = 10.11.11 fail to properly validate user identity in the OpenID IsSameUser comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user...

Incorrect Implementation of Authentication Algorithm

Overview github.com/mattermost/mattermost-server is an open source Slack-alternative in Golang and React. Affected versions of this package are vulnerable to Incorrect Implementation of Authentication Algorithm in the IsSameUser function. An attacker can gain unauthorized access to arbitrary user...

GHSA-FG35-5RF6-QG3G Mattermost allows attackers to take over arbitrary user accounts via overly permissive substring matching flaw

Mattermost versions 11.4.x = 11.4.0, 11.3.x = 11.3.1, 11.2.x = 11.2.3, 10.11.x = 10.11.11 fail to properly validate user identity in the OpenID IsSameUser comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user...

CVE-2026-27656

Mattermost versions 11.4.x = 11.4.0, 11.3.x = 11.3.1, 11.2.x = 11.2.3, 10.11.x = 10.11.11 fail to properly validate user identity in the OpenID IsSameUser comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user...

CVE-2026-27656

Mattermost versions 11.4.x = 11.4.0, 11.3.x = 11.3.1, 11.2.x = 11.2.3, 10.11.x = 10.11.11 fail to properly validate user identity in the OpenID IsSameUser comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user...

CVE-2026-27656 Account Takeover via Substring Matching in OpenID Connect Authentication

Mattermost versions 11.4.x = 11.4.0, 11.3.x = 11.3.1, 11.2.x = 11.2.3, 10.11.x = 10.11.11 fail to properly validate user identity in the OpenID IsSameUser comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user...

CVE-2026-27656 Account Takeover via Substring Matching in OpenID Connect Authentication

Mattermost versions 11.4.x = 11.4.0, 11.3.x = 11.3.1, 11.2.x = 11.2.3, 10.11.x = 10.11.11 fail to properly validate user identity in the OpenID IsSameUser comparison logic, which allows an attacker to take over arbitrary user accounts via an overly permissive substring matching flaw in the user...

CVE-2026-27656

Mattermost contains a vulnerability (CVE-2026-27656) where versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, and 10.11.x

Security update for postgresql17

This update for postgresql17 fixes the following issues: Update to version 17.9 bsc1258754. Security issues fixed: CVE-2026-2003: improper validation of type "oidvector" may allow disclose a few bytes of server memory bsc1258008. CVE-2026-2004: intarray missing validation of type of input to...

SUSE-SU-2026:0883-1 Security update for postgresql17

This update for postgresql17 fixes the following issues: Update to version 17.9 bsc1258754. Security issues fixed: - CVE-2026-2003: improper validation of type 'oidvector' may allow disclose a few bytes of server memory bsc1258008. - CVE-2026-2004: intarray missing validation of type of input to...

Security update for postgresql16

This update for postgresql16 fixes the following issues: Update to version 16.13 bsc1258754. Security issues fixed: CVE-2026-2003: improper validation of type "oidvector" may allow disclose a few bytes of server memory bsc1258008. CVE-2026-2004: intarray missing validation of type of input to...

SUSE: Security Advisory (SUSE-SU-2026:0787-1)

The remote host is missing an update for the SPDX-FileCopyrightText: 2026 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

SUSE: Security Advisory (SUSE-SU-2026:0769-1)

The remote host is missing an update for the SPDX-FileCopyrightText: 2026 Greenbone AG Some text descriptions might be excerpted from a referenced sources, and are Copyright C by the respective right holders. SPDX-License-Identifier: GPL-2.0-only ifdescription...

SUSE SLES15 Security Update : postgresql16 (SUSE-SU-2026:0784-1)

The remote SUSE Linux SLES15 / SLESSAP15 host has packages installed that are affected by a vulnerability as referenced in the SUSE-SU-2026:0784-1 advisory. This update for postgresql16 fixes the following issue: Update to version 16.13 bsc1258754. Regression fixes: - the substring function raise...

Security update for postgresql17

This update for postgresql17 fixes the following issue: Update to version 17.9 bsc1258754. Regression fixes: the substring function raises an error "invalid byte sequence for encoding" on non-ASCII text values if the source of that value is a database column caused by CVE-2026-2006 fix. a standby...

SUSE-SU-2026:0787-1 Security update for postgresql17

This update for postgresql17 fixes the following issue: Update to version 17.9 bsc1258754. Regression fixes: - the substring function raises an error 'invalid byte sequence for encoding' on non-ASCII text values if the source of that value is a database column caused by CVE-2026-2006 fix. - a...

SUSE-SU-2026:0786-1 Security update for postgresql14

This update for postgresql14 fixes the following issues: Update to version 14.22 bsc1258754. Security issues fixed: - CVE-2026-2003: improper validation of type 'oidvector' may allow disclose a few bytes of server memory bsc1258008. - CVE-2026-2004: intarray missing validation of type of input to...

Security update for postgresql18

This update for postgresql18 fixes the following issue: Update to version 18.3 bsc1258754. Regression fixes: the substring function raises an error "invalid byte sequence for encoding" on non-ASCII text values if the source of that value is a database column caused by CVE-2026-2006 fix. a standby...

SUSE-SU-2026:0785-1 Security update for postgresql18

This update for postgresql18 fixes the following issue: Update to version 18.3 bsc1258754. Regression fixes: - the substring function raises an error 'invalid byte sequence for encoding' on non-ASCII text values if the source of that value is a database column caused by CVE-2026-2006 fix. - a...

SUSE-SU-2026:0784-1 Security update for postgresql16

This update for postgresql16 fixes the following issue: Update to version 16.13 bsc1258754. Regression fixes: - the substring function raises an error 'invalid byte sequence for encoding' on non-ASCII text values if the source of that value is a database column caused by CVE-2026-2006 fix. - a...