Envoy is a cloud-native, open source edge and service proxy. A crash was observed in `EnvoyQuicServerStream::OnInitialHeadersComplete()` with following call stack. It is a use-after-free caused by QUICHE continuing push request headers after `StopReading()` being called on the stream. As after `StopReading()`, the HCM's `ActiveStream` might have already be destroyed and any up calls from QUICHE could potentially cause use after free.

Envoy is a cloud-native, open source edge and service proxy. A theoretical request smuggling vulnerability exists through Envoy if a server can be tricked into adding an upgrade header into a response. Per RFC https://www.rfc-editor.org/rfc/rfc7230#section-6.7 a server sends 101 when switching protocols. Envoy incorrectly accepts a 200 response from a server when requesting a protocol upgrade, but 200 does not indicate protocol switch. This opens up the possibility of request smuggling through Envoy if the server can be tricked into adding the upgrade header to the response.

The Envo Extra plugin for WordPress is vulnerable to Stored Cross-Site Scripting via multiple parameters in versions up to, and including, 1.8.16 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with contributor-level permissions and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in EnvoThemes Envo's Elementor Templates & Widgets for WooCommerce allows Stored XSS.This issue affects Envo's Elementor Templates & Widgets for WooCommerce: from n/a through 1.4.8.

Envoy is a cloud-native, open source edge and service proxy. When an upstream TLS cluster is used with `auto_sni` enabled, a request containing a `host`/`:authority` header longer than 255 characters triggers an abnormal termination of Envoy process. Envoy does not gracefully handle an error when setting SNI for outbound TLS connection. The error can occur when Envoy attempts to use the `host`/`:authority` header value longer than 255 characters as SNI for outbound TLS connection. SNI length is limited to 255 characters per the standard. Envoy always expects this operation to succeed and abnormally aborts the process when it fails. This vulnerability is fixed in 1.30.1, 1.29.4, 1.28.3, and 1.27.5.

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in EnvoThemes Envo Extra allows Stored XSS.This issue affects Envo Extra: from n/a through 1.8.11.

Envoy is a cloud-native, open source edge and service proxy. The HTTP/2 protocol stack in Envoy versions prior to 1.29.3, 1.28.2, 1.27.4, and 1.26.8 are vulnerable to CPU exhaustion due to flood of CONTINUATION frames. Envoy's HTTP/2 codec allows the client to send an unlimited number of CONTINUATION frames even after exceeding Envoy's header map limits. This allows an attacker to send a sequence of CONTINUATION frames without the END_HEADERS bit set causing CPU utilization, consuming approximately 1 core per 300Mbit/s of traffic and culminating in denial of service through CPU exhaustion. Users should upgrade to version 1.29.3, 1.28.2, 1.27.4, or 1.26.8 to mitigate the effects of the CONTINUATION flood. As a workaround, disable HTTP/2 protocol for downstream connections.

Envoy is a cloud-native, open-source edge and service proxy. In versions 1.29.0 and 1.29.1, theEnvoy HTTP/2 protocol stack is vulnerable to the flood of CONTINUATION frames. Envoy's HTTP/2 codec does not reset a request when header map limits have been exceeded. This allows an attacker to send an sequence of CONTINUATION frames without the END_HEADERS bit set causing unlimited memory consumption. This can lead to denial of service through memory exhaustion. Users should upgrade to versions 1.29.2 to mitigate the effects of the CONTINUATION flood. Note that this vulnerability is a regression in Envoy version 1.29.0 and 1.29.1 only. As a workaround, downgrade to version 1.28.1 or earlier or disable HTTP/2 protocol for downstream connections.

The Envo's Elementor Templates & Widgets for WooCommerce plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to and including 1.4.4. This is due to missing or incorrect nonce validation on the ajax_theme_activation function. This makes it possible for unauthenticated attackers to activate arbitrary installed themes via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.

The Envo's Elementor Templates & Widgets for WooCommerce plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 1.4.4. This is due to missing or incorrect nonce validation on the ajax_plugin_activation function. This makes it possible for unauthenticated attackers to activate arbitrary installed plugins via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.