CVE-2023-47119

Table of contents CVE-2023-47119 Detailed analysis POC Escalation ? LAB Setup CVE-2023-47119 A POC for CVE-2023-47119 which is a vulnerability affecting Discourse versions prior to version 3.1.3 of the stable branch and version 3.2.0.beta3 of the beta and tests-passed branches. Some links can...

BIT-DISCOURSE-2026-91132 Discourse: Wildcard iframe origin allowlist bypass via authority separators

Discourse is an open-source discussion platform. Prior to 2026.1.8, 2026.6.3, 2026.7.2, and 2026.8.0, sites using wildcard patterns in the allowediframes setting could accept a crafted iframe URL whose allowlisted suffix appeared after a URL authority separator. The wildcard origin check matched...

PT-2026-98161

Name of the Vulnerable Software and Affected Versions Discourse versions prior to 2026.1.8 Discourse versions prior to 2026.6.3 Discourse versions prior to 2026.7.2 Discourse versions prior to 2026.8.0 Description Sites using wildcard patterns in the allowed iframes setting may accept a crafted...

BIT-DISCOURSE-2026-72728 Discourse: Onebox iframe origin allowlist enforces URL authority boundary

Discourse is an open-source discussion platform. Prior to 2026.1.7, an authenticated user could submit specially formed URLs that bypassed the Onebox allowlist and embedded malicious content in a site. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0...

BIT-DISCOURSE-2026-72724 Discourse: Private Chat Threat Message Disclosure via Chat Onebox Channel/Threat ID Mismatch

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, plugins/chat/lib/chat/oneboxhandler.rb resolves Chat::Thread by route threadid independently of the route channelid before checking whether the user can preview the selected chat channel. An...

BIT-DISCOURSE-2026-72721 Discourse: Onebox Domain Blocklist Bypass via Case-Sensitive Comparison

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, Onebox::DomainChecker.isblocked? compares hostnames and SiteSetting.blockedoneboxdomains entries case-sensitively, allowing an attacker to bypass configured Onebox domain restrictions by changing...

PT-2026-73255

Discourse is an open-source discussion platform. Prior to 2026.1.7, an authenticated user could submit specially formed URLs that bypassed the Onebox allowlist and embedded malicious content in a site. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0...

PT-2026-73248

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, Onebox::DomainChecker.is blocked? compares hostnames and SiteSetting.blocked onebox domains entries case-sensitively, allowing an attacker to bypass configured Onebox domain restrictions by...

PT-2026-73251

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, plugins/chat/lib/chat/onebox handler.rb resolves Chat::Thread by route thread id independently of the route channel id before checking whether the user can preview the selected chat channel. An...

CVE-2026-72721

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, Onebox::DomainChecker.isblocked? compares hostnames and SiteSetting.blockedoneboxdomains entries case-sensitively, allowing an attacker to bypass configured Onebox domain restrictions by changing...

CVE-2026-72724

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, plugins/chat/lib/chat/oneboxhandler.rb resolves Chat::Thread by route threadid independently of the route channelid before checking whether the user can preview the selected chat channel. An...

CVE-2026-72728 Discourse: Onebox iframe origin allowlist enforces URL authority boundary

Discourse is an open-source discussion platform. Prior to 2026.1.7, an authenticated user could submit specially formed URLs that bypassed the Onebox allowlist and embedded malicious content in a site. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0-latest.1...

EUVD-2026-55667

Discourse is an open-source discussion platform. Prior to 2026.1.7, an authenticated user could submit specially formed URLs that bypassed the Onebox allowlist and embedded malicious content in a site. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0-latest.1...

CVE-2026-72728 Discourse: Onebox iframe origin allowlist enforces URL authority boundary

Discourse is an open-source discussion platform. Prior to 2026.1.7, an authenticated user could submit specially formed URLs that bypassed the Onebox allowlist and embedded malicious content in a site. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0-latest.1...

CVE-2026-72728 Discourse: Onebox iframe origin allowlist enforces URL authority boundary

Discourse is an open-source discussion platform. Prior to 2026.1.7, an authenticated user could submit specially formed URLs that bypassed the Onebox allowlist and embedded malicious content in a site. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0-latest.1...

CVE-2026-72728

Discourse pre-2026.1.7 is affected by a Onebox iframe origin allowlist bypass. An authenticated user could submit specially formed URLs that bypassed the allowlist and embedded malicious content in a site. Affected component is the Onebox URL handling; root cause is improper enforcement of the UR...

EUVD-2026-55663

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, plugins/chat/lib/chat/oneboxhandler.rb resolves Chat::Thread by route threadid independently of the route channelid before checking whether the user can preview the selected chat channel. An...

CVE-2026-72724 Discourse: Private Chat Threat Message Disclosure via Chat Onebox Channel/Threat ID Mismatch

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, plugins/chat/lib/chat/oneboxhandler.rb resolves Chat::Thread by route threadid independently of the route channelid before checking whether the user can preview the selected chat channel. An...

CVE-2026-72724

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, plugins/chat/lib/chat/oneboxhandler.rb resolves Chat::Thread by route threadid independently of the route channelid before checking whether the user can preview the selected chat channel. An...

CVE-2026-72724

Discourse vulnerability CVE-2026-72724 affects the chat onebox flow. Prior to versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, plugins/chat/lib/chat/onebox_handler.rb resolves Chat::Thread by route thread_id independently of the route channel_id before verifying preview permissions, allowing ...