Where
AND
-Infinity
0
Severity
8.6
EPSS
0.05%
Input Validation
AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

Envoy is a high-performance edge/middle/service proxy. External authentication can be bypassed by downstream connections. Downstream clients can force invalid gRPC requests to be sent to extauthz, circumventing extauthz checks when failuremodeallow is set to true. This issue has been addressed in released 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

First published (updated )
Severity
7.5
EPSS
0.05%
Null Pointer Dereference
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Envoy is a high-performance edge/middle/service proxy. When PPv2 is enabled both on a listener and subsequent cluster, the Envoy instance will segfault when attempting to craft the upstream PPv2 header. This occurs when the downstream request has a command type of LOCAL and does not have the protocol block. This issue has been addressed in releases 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

First published (updated )
Severity
7.5
EPSS
0.05%
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Envoy is a high-performance edge/middle/service proxy. Envoy crashes in Proxy protocol when using an address type that isn’t supported by the OS. Envoy is susceptible to crashing on a host with IPv6 disabled and a listener config with proxy protocol enabled when it receives a request where the client presents its IPv6 address. It is valid for a client to present its IPv6 address to a target server even though the whole chain is connected via IPv4. This issue has been addressed in released 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

First published (updated )
Severity
7.5
EPSS
0.05%
Use After Free
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Envoy is a high-performance edge/middle/service proxy. Envoy will crash when certain timeouts happen within the same interval. The crash occurs when the following are true: 1. hedgeonpertrytimeout is enabled, 2. pertryidletimeout is enabled (it can only be done in configuration), 3. per-try-timeout is enabled, either through headers or configuration and its value is equal, or within the backoff interval of the pertryidletimeout. This issue has been addressed in released 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

First published (updated )
Severity
7.5
EPSS
0.04%
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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 ENDHEADERS 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.

1 / 2
Source: MITRE
First published (updated )
Severity
7.5
EPSS
0.04%
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Envoy is a cloud-native, open source edge and service proxy. When an upstream TLS cluster is used with autosni 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.

1 / 2
Source: MITRE
First published (updated )
Severity
7.5
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Envoy is a cloud-native, open source edge and service proxy. Due to how Envoy invoked the nlohmann JSON library, the library could throw an uncaught exception from downstream data if incomplete UTF-8 strings were serialized. The uncaught exception would cause Envoy to crash.

First published (updated )
Severity
7.5
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Envoy is a cloud-native, open source edge and service proxy. Envoyproxy with a Brotli filter can get into an endless loop during decompression of Brotli data with extra input.

1 / 2
Source: MITRE
First published (updated )
Severity
7.5
Use After Free
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

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.

First published (updated )
Severity
7.5
Integer Underflow
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Envoy is a cloud-native, open source edge and service proxy. There is a crash at QuicheDataReader::PeekVarInt62Length(). It is caused by integer underflow in the QuicStreamSequencerBuffer::PeekRegion() implementation.

First published (updated )
Severity
6.5
AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H

Envoy is a cloud-native, open source edge and service proxy. Envoy exposed an out-of-memory (OOM) vector from the mirror response, since async HTTP client will buffer the response with an unbounded buffer.

First published (updated )
Severity
5.9
Use After Free
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Envoy is a cloud-native, open source edge and service proxy. There is a use-after-free in HttpConnectionManager (HCM) with EnvoyQuicServerStream that can crash Envoy. An attacker can exploit this vulnerability by sending a request without FIN, then a RESETSTREAM frame, and then after receiving the response, closing the connection.

First published (updated )
Severity
5.3
EPSS
0.05%
AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

Envoy is a high-performance edge/middle/service proxy. The regex expression is compiled for every request and can result in high CPU usage and increased request latency when multiple routes are configured with such matchers. This issue has been addressed in released 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.

First published (updated )

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