Mattermost 5.38 and earlier fails to sufficiently sanitize clipboard contents, which allows a user-assisted attacker to inject arbitrary web script in product deployments that explicitly disable the default CSP.

Fixed a bypass for a reflected cross-site scripting vulnerability affecting OAuth-enabled instances of Mattermost.

Mattermost version 8.1.6 and earlier fails to sanitize channel mention data in posts, which allows an attacker to inject markup in the web client.

An issue was discovered in Mattermost Server before 4.0.0, 3.10.2, and 3.9.2. It allows XSS via an uploaded file.

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. XSS attacks could occur against an OAuth 2.0 allow/deny page.

An issue was discovered in Mattermost Server before 4.0.0, 3.10.2, and 3.9.2. XSS could occur via a channel header.

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. XSS can occur via OpenGraph data.

An issue was discovered in Mattermost Server before 3.5.1. XSS can occur via file preview.

An issue was discovered in Mattermost Server before 2.2.0. It allows XSS because it configures files to be opened in a browser window.

An issue was discovered in Mattermost Server before 3.0.0. It allows XSS via a Legal or Support setting.

An issue was discovered in Mattermost Server before 3.1.0. It allows XSS because the noreferrer and noopener protection mechanisms were not in place.

An issue was discovered in Mattermost Server before 2.2.0. It allows XSS via a crafted link.

An issue was discovered in Mattermost Server before 3.8.2, 3.7.5, and 3.6.7. XSS can occur via a link on an error page.

A reflected cross-site scripting vulnerability in the OAuth flow completion endpoints in Mattermost allows an attacker to send AJAX requests on behalf of the victim via sharing a crafted link with a malicious state parameter.

Mattermost Jira plugin versions shipped with Mattermost versions 8.1.x before 8.1.10, 9.2.x before 9.2.6, 9.3.x before 9.3.2, and 9.4.x before 9.4.3 fail to escape user-controlled outputs when generating HTML pages, which allows an attacker to perform reflected cross-site scripting attacks against the users of the Mattermost server.

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. XSS could occur via the title_link field of a Slack attachment.

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. XSS could occur via the author_link field of a Slack attachment.

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. XSS could occur via a goto_location response to a slash command.

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. Display names allow XSS.

An issue was discovered in Mattermost Server before 3.6.0 and 3.5.2. XSS can occur via a link on an error page.

An issue was discovered in Mattermost Desktop App before 4.4.0. Attackers can open web pages in the desktop application because server redirection is mishandled, aka MMSA-2020-0008.

An issue was discovered in Mattermost Server before 5.18.0, 5.17.2, 5.16.4, 5.15.4, and 5.9.7. An attacker can spoof a direct-message channel by changing the type of a channel.

Mattermost fails to properly check a redirect URL parameter allowing for an open redirect was possible when the user clicked "Back to Mattermost" after providing a invalid custom url scheme in /oauth/{service}/mobile_login?redirect_to=

Mattermost Desktop App versions <=5.7.0 fail to correctly prompt for permission when opening external URLs which allows a remote attacker to force a victim over the Internet to run arbitrary programs on the victim's system via custom URI schemes.

An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows an attacker to create a button that, when pressed by a user, launches an API request.

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. It allows Phishing because an error page can have a link.

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5. E-mail templates can have a field in which HTML content is not neutralized.

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5, when used as an OAuth 2.0 service provider. It mishandles a deny action for a redirection.

An issue was discovered in Mattermost Server before 2.1.0. It allows XSS via CSRF.

Mattermost versions 10.11.x <= 10.11.4 fail to validate redirect URLs on the /error page, which allows an attacker to redirect a victim to a malicious site via a crafted link opened in a new tab.

Mattermost versions 10.5.x <= 10.5.9 fail to properly validate redirect URLs which allows attackers to redirect users to malicious sites via crafted OAuth login URLs

Boards in Mattermost allows an attacker to upload a malicious SVG image file as an attachment to a card and share it using a direct link to the file.

An issue was discovered in Mattermost Server before 3.1.0. It allows XSS via theme color-code values.

Mattermost Confluence plugin version <1.7.0 fails to properly escape user-controlled display names in HTML template rendering which allows authenticated Confluence users with malicious display names to execute arbitrary JavaScript in victim browsers via sending a specially crafted OAuth2 connection link that, when visited, renders the attacker's display name without proper sanitization. Mattermost Advisory ID: MMSA-2025-00557

Mattermost 6.3.0 and earlier fails to properly sanitize the HTML content in the email invitation sent to guest users, which allows registered users with special permissions to invite guest users to inject unescaped HTML content in the email invitations.

Sonatype Nexus Repository Manager OSS/Pro versions before 3.25.1 allow XSS (issue 1 of 2).

Cross-site scripting (XSS) vulnerability in view.php in Pulse CMS 1.2.2 allows remote attackers to inject arbitrary web script or HTML via the f parameter.

PHP Education Manager v1.0 is vulnerable to Cross Site Scripting (XSS) in the worksheet.php file via the participant_name parameter.

Cross-site scripting (XSS) vulnerability in WebKit in Apple Safari before 5.0 on Mac OS X 10.5 through 10.6 and Windows, and before 4.1 on Mac OS X 10.4, allows remote attackers to inject arbitrary web script or HTML via vectors involving DOM constructor objects, related to a "scope management issue."

Cross-site scripting (XSS) vulnerability in _layouts/help.aspx in Microsoft SharePoint Server 2007 12.0.0.6421 and possibly earlier, and SharePoint Services 3.0 SP1 and SP2, versions, allows remote attackers to inject arbitrary web script or HTML via the cid0 parameter.

Cross-site scripting (XSS) vulnerability in ShowPost.asp in BBSXP 2008 allows remote attackers to inject arbitrary web script or HTML via the ThreadID parameter.

Cross-site scripting (XSS) vulnerability in NOCC 0.9 through 0.9.5 allows remote attackers to inject arbitrary web script or HTML via email messages.

Cross-site scripting (XSS) vulnerability in projects.php in Scratcher allows remote attackers to inject arbitrary web script or HTML via the show parameter.

Cross-site scripting (XSS) vulnerability in admin/editprefs.php in the backend in CMS Made Simple (CMSMS) before 1.7.1 might allow remote attackers to inject arbitrary web script or HTML via the date_format_string parameter.

Multiple cross-site scripting (XSS) vulnerabilities in HP Insight Control Server Migration before 6.0 allow remote attackers to inject arbitrary web script or HTML via unspecified vectors.

Mahara before 25.04.2 and 24.04.11 are vulnerable to displaying results that can trigger XSS via a malicious search query string. This occurs in the 'search site' feature when using the Elasticsearch7 search plugin. The Elasticsearch function does not properly sanitize input in the query parameter.

Multiple cross-site scripting (XSS) vulnerabilities in _invoice.asp in CactuShop before 6.155 allow remote attackers to inject arbitrary web script or HTML via the (1) billing address or (2) shipping address.

Firefox sometimes ran the onload handler for SVG elements that the DOM sanitizer decided to remove, resulting in JavaScript being executed after pasting attacker-controlled data into a contenteditable element. This vulnerability affects Firefox < 81, Thunderbird < 78.3, and Firefox ESR < 78.3.

Multiple cross-site scripting (XSS) vulnerabilities in Atlassian JIRA 3.12 through 4.1 allow remote attackers to inject arbitrary web script or HTML via the (1) element or (2) defaultColor parameter to the Colour Picker page; the (3) formName parameter, (4) element parameter, or (5) full name field to the User Picker page; the (6) formName parameter, (7) element parameter, or (8) group name field to the Group Picker page; the (9) announcement_preview_banner_st parameter to unspecified components, related to the Announcement Banner Preview page; unspecified vectors involving the (10) groupnames.jsp, (11) indexbrowser.jsp, (12) classpath-debug.jsp, (13) viewdocument.jsp, or (14) cleancommentspam.jsp page; the (15) portletKey parameter to runportleterror.jsp; the (16) URI to issuelinksmall.jsp; the (17) afterURL parameter to screenshot-redirecter.jsp; or the (18) HTTP Referrer header to 500page.jsp, as exploited in the wild in April 2010.

phpPgAdmin 7.13.0 and earlier contains multiple cross-site scripting (XSS) vulnerabilities across various components. User-supplied input from $_REQUEST parameters is reflected in HTML output without proper encoding or sanitization in multiple locations including sequences.php, indexes.php, admin.php, and other unspecified files. An attacker can exploit these vulnerabilities to execute arbitrary JavaScript in victims' browsers, potentially leading to session hijacking, credential theft, or other malicious actions.