CVE-2026-73321

XenForo before 2.3.13 contains an uncontrolled recursion vulnerability in the BBCode parser that allows authenticated attackers to cause persistent denial of service by submitting a post with deeply nested BBCode tags. Attackers can craft a single malicious post with sufficient nesting depth to...

CVE-2026-73315

XenForo before 2.3.13 contains a server-side request forgery vulnerability in the PayPal REST webhook handler that allows unauthenticated attackers to cause the server to make outbound HTTP requests to arbitrary destinations by supplying a crafted certificate URL in webhook headers without scheme...

CVE-2026-73312

XenForo before 2.3.13 contains a refresh token replay vulnerability that allows attackers to reuse a refresh token multiple times by exploiting the failure to mark tokens as consumed when the parent access token has expired. Attackers can repeatedly submit the same refresh token to generate...

CVE-2026-73316

XenForo before 2.3.13 contains a payment replay vulnerability in the PayPal REST payment provider that allows attackers to process the same webhook payload multiple times by exploiting a missing duplicate transaction ID check. Attackers can replay a valid webhook payload to trigger duplicate...

CVE-2026-73311

XenForo before 2.3.13 contains an OAuth2 authorization code reuse vulnerability that allows attackers to obtain unauthorized token pairs by submitting a previously used authorization code. Attackers can exploit the failure to invalidate or mark authorization codes as consumed after initial token...

CVE-2026-73314

XenForo before 2.3.13 contains a signature verification logic error in the PayPal REST webhook handler that allows unauthenticated attackers to bypass payment signature validation by submitting a webhook request with an unsupported authalgo header value. When the algorithm cannot be mapped to a...

CVE-2026-73310

XenForo before 2.3.13 contains an authorization flaw in the OAuth2 token endpoint that allows attackers controlling any allowlisted redirect URI to bypass redirect URI binding by submitting a different allowlisted URI than the one recorded at authorization time. Attackers can exchange an...

CVE-2026-73313

XenForo before 2.3.13 contains a multi-factor authentication bypass vulnerability in the passkey TFA provider that allows an authenticated attacker to complete login as another user by submitting their own registered passkey credential during the WebAuthn assertion step. The passkey verification...

CVE-2026-73309

XenForo before 2.3.13 contains an authentication bypass vulnerability in the OAuth2 token endpoint that allows unauthenticated attackers to obtain valid token pairs by submitting empty values for clientsecret and codeverifier parameters. Attackers can exploit PHP truthy evaluation logic, which...

CVE-2026-74239

XenForo before 2.3.13 is affected by a path traversal vulnerability in the style archive importer on Windows deployments. Authenticated non-super administrators with style permissions can exploit backslash-based traversal sequences in ZIP member names to bypass forward-slash validation, writing a...

CVE-2026-74239 XenForo < 2.3.13 Path Traversal via Style Archive Importer on Windows

XenForo before 2.3.13 contains a path traversal vulnerability in the style archive importer on Windows deployments that allows authenticated non-super administrators with style permissions to write arbitrary files outside the intended extraction directory by using backslash-based traversal...

EUVD-2026-72759

XenForo before 2.3.13 contains a path traversal vulnerability in the style archive importer on Windows deployments that allows authenticated non-super administrators with style permissions to write arbitrary files outside the intended extraction directory by using backslash-based traversal...

CVE-2026-74239 XenForo < 2.3.13 Path Traversal via Style Archive Importer on Windows

XenForo before 2.3.13 contains a path traversal vulnerability in the style archive importer on Windows deployments that allows authenticated non-super administrators with style permissions to write arbitrary files outside the intended extraction directory by using backslash-based traversal...

EUVD-2026-72758

XenForo before 2.3.13 contains an uncontrolled recursion vulnerability in the BBCode parser that allows authenticated attackers to cause persistent denial of service by submitting a post with deeply nested BBCode tags. Attackers can craft a single malicious post with sufficient nesting depth to...

CVE-2026-73321 XenForo < 2.3.13 Uncontrolled Recursion DoS via BBCode Parser

XenForo before 2.3.13 contains an uncontrolled recursion vulnerability in the BBCode parser that allows authenticated attackers to cause persistent denial of service by submitting a post with deeply nested BBCode tags. Attackers can craft a single malicious post with sufficient nesting depth to...

CVE-2026-73321

XenForo before 2.3.13 contains an uncontrolled recursion vulnerability in the BBCode parser . Authenticated attackers can submit a single post with deeply nested BBCode tags sufficient to exceed PHP's stack limit, causing fatal errors that repeatedly terminate PHP-FPM workers for all visitors ren...

EUVD-2026-72757

XenForo before 2.3.13 contains an unauthenticated information disclosure vulnerability that allows unauthenticated attackers to retrieve private unfurl records by supplying predictable auto-increment primary key IDs to the unfurl endpoint. Attackers can enumerate or predict result IDs and query t...

CVE-2026-73320 XenForo < 2.3.13 Unauthenticated Information Disclosure via Unfurl Endpoint

XenForo before 2.3.13 contains an unauthenticated information disclosure vulnerability that allows unauthenticated attackers to retrieve private unfurl records by supplying predictable auto-increment primary key IDs to the unfurl endpoint. Attackers can enumerate or predict result IDs and query t...

CVE-2026-73320

XenForo before 2.3.13 is affected by an unauthenticated information disclosure vulnerability in the unfurl endpoint . Attackers can supply predictable auto-increment primary key IDs to retrieve rendered preview HTML, original URLs, and query strings from private conversations and other restricted...

CVE-2026-73320 XenForo < 2.3.13 Unauthenticated Information Disclosure via Unfurl Endpoint

XenForo before 2.3.13 contains an unauthenticated information disclosure vulnerability that allows unauthenticated attackers to retrieve private unfurl records by supplying predictable auto-increment primary key IDs to the unfurl endpoint. Attackers can enumerate or predict result IDs and query t...