
CVE-2021-32780 – Incorrect handling of H/2 GOAWAY followed by SETTINGS frames
https://notcve.org/view.php?id=CVE-2021-32780
24 Aug 2021 — Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions Envoy transitions a H/2 connection to the CLOSED state when it receives a GOAWAY frame without any streams outstanding. The connection state is transitioned to DRAINING when it receives a SETTING frame with the SETTINGS_MAX_CONCURRENT_STREAMS parameter set to 0. Receiving these two frames in the same I/O event results in abnormal termination of the Envoy process due to invali... • https://github.com/envoyproxy/envoy/security/advisories/GHSA-j374-mjrw-vvp8 • CWE-754: Improper Check for Unusual or Exceptional Conditions •

CVE-2021-32781 – Continued processing of requests after locally generated response
https://notcve.org/view.php?id=CVE-2021-32781
24 Aug 2021 — Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions after Envoy sends a locally generated response it must stop further processing of request or response data. However when local response is generated due the internal buffer overflow while request or response is processed by the filter chain the operation may not be stopped completely and result in accessing a freed memory block. A specifically constructed request delivered by... • https://github.com/envoyproxy/envoy/security/advisories/GHSA-5vhv-gp9v-42qv • CWE-120: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') CWE-416: Use After Free CWE-476: NULL Pointer Dereference •

CVE-2021-32779 – Incorrectly handling of URI '#fragment' element as part of the path element
https://notcve.org/view.php?id=CVE-2021-32779
24 Aug 2021 — Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions envoy incorrectly handled a URI '#fragment' element as part of the path element. Envoy is configured with an RBAC filter for authorization or similar mechanism with an explicit case of a final "/admin" path element, or is using a negative assertion with final path element of "/admin". The client sends request to "/app1/admin#foo". In Envoy prior to 1.18.0, or 1.18.0+ configur... • https://github.com/envoyproxy/envoy/security/advisories/GHSA-r222-74fw-jqr9 • CWE-551: Incorrect Behavior Order: Authorization Before Parsing and Canonicalization CWE-697: Incorrect Comparison CWE-863: Incorrect Authorization •

CVE-2021-32778 – Excessive CPU utilization when closing HTTP/2 streams
https://notcve.org/view.php?id=CVE-2021-32778
24 Aug 2021 — Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions envoy’s procedure for resetting a HTTP/2 stream has O(N^2) complexity, leading to high CPU utilization when a large number of streams are reset. Deployments are susceptible to Denial of Service when Envoy is configured with high limit on H/2 concurrent streams. An attacker wishing to exploit this vulnerability would require a client opening and closing a large number of H/2 s... • https://github.com/envoyproxy/envoy/security/advisories/GHSA-3xh3-33v5-chcc • CWE-834: Excessive Iteration •

CVE-2021-32777 – Incorrect concatenation of multiple value request headers in ext-authz extension
https://notcve.org/view.php?id=CVE-2021-32777
24 Aug 2021 — Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In affected versions when ext-authz extension is sending request headers to the external authorization service it must merge multiple value headers according to the HTTP spec. However, only the last header value is sent. This may allow specifically crafted requests to bypass authorization. Attackers may be able to escalate privileges when using ext-authz extension or back end service that uses mu... • https://github.com/envoyproxy/envoy/security/advisories/GHSA-6g4j-5vrw-2m8h • CWE-551: Incorrect Behavior Order: Authorization Before Parsing and Canonicalization CWE-863: Incorrect Authorization •

CVE-2021-29492 – Bypass of path matching rules using escaped slash characters
https://notcve.org/view.php?id=CVE-2021-29492
12 May 2021 — Envoy is a cloud-native edge/middle/service proxy. Envoy does not decode escaped slash sequences `%2F` and `%5C` in HTTP URL paths in versions 1.18.2 and before. A remote attacker may craft a path with escaped slashes, e.g. `/something%2F..%2Fadmin`, to bypass access control, e.g. a block on `/admin`. A backend server could then decode slash sequences and normalize path and provide an attacker access beyond the scope provided for by the access control policy. ### Impact Escalation of Privileges when using R... • https://github.com/envoyproxy/envoy/security/advisories/GHSA-4987-27fx-x6cf • CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE-863: Incorrect Authorization •