CVE-2026-55213 h2o: musl libc stack overflow (QPACK)

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit edd7a120bfc4af11ac0cbebce2a43cc1f93f9af1, when h2o processes a QPACK instruction sent from the peer over HTTP/3, lib/http3/qpack.c might allocate an on-stack buffer as large as approximately 800 KB by calling...

Unpatched XRING Flaw in XQUIC Lets Remote Clients Crash HTTP/3 Servers

A single wrong variable on one line in XQUIC, Alibaba's QUIC and HTTP/3 library, lets any remote client crash the server with a short burst of completely legal traffic. There is no patch. FoxIO researcher Sébastien Féry disclosed the flaw on July 8 and nicknamed it XRING. He says it needs no logi...

PT-2026-57321

Name of the Vulnerable Software and Affected Versions h2o versions prior to commit edd7a120bfc4af11ac0cbebce2a43cc1f93f9af1 Description When processing a QPACK instruction sent from a peer over HTTP/3, the server may allocate an on-stack buffer of approximately 800 KB using the alloca function in...

BIT-NGINX-GATEWAY-2026-42530 NGINX Open-Source ngx_http_v3_module vulnerability

NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This m...

nginx 1.31.x < 1.31.2 Use-After-Free Vulnerability

The installed version of nginx is 1.31.x prior to 1.31.2. It is, therefore, affected by the following vulnerability: - NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along...

The vulnerability of the io.netty.handler.codec.http3.QpackDecoder component in the Netty framework, which is used for developing network applications, servers, and clients. This vulnerability allows a attacker to cause a service failure.

The vulnerability of the io.netty.handler.codec.http3.QpackDecoder component in the Netty framework, which is used for developing network applications, servers, and clients, involves unlimited distribution of resources. Exploiting this vulnerability can allow a malicious actor to cause service...

CVE-2026-42530

NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This m...

DEBIAN-CVE-2026-42530

NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This m...

CVE-2026-42530

NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This m...

CVE-2026-42530

NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This m...

CVE-2026-42530 NGINX Open-Source ngx_http_v3_module vulnerability

NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This m...

EUVD-2026-37717

NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This m...

CVE-2026-42530

Summary : NGINX Open Source’s ngx_http_v3_module vulnerability (CVE-2026-42530) occurs when HTTP/3 QUIC is enabled. A remote unauthenticated attacker can craft an HTTP/3 session to reopen a QPACK encoder stream, causing a Use-after-Free in the NGINX worker process and potentially triggering a res...

CVE-2026-42530 NGINX Open-Source ngx_http_v3_module vulnerability

NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This m...

CVE-2026-42530

NGINX Open Source has a vulnerability in the ngxhttpv3module module. When NGINX Open Source is configured to use the HTTP/3 QUIC module, a remote unauthenticated attacker along with conditions beyond their control can use a specially crafted HTTP/3 session to reopen a QPACK encoder stream. This m...

PT-2026-50439

Name of the Vulnerable Software and Affected Versions NGINX Open Source versions 1.31.0 through 1.31.1 NGINX Ingress Controller affected versions not specified NGINX Gateway Fabric affected versions not specified NGINX Instance Manager affected versions not specified Description A use-after-free...

GHSA-4GRM-H2QV-H6W6 Netty HTTP/3 QPACK Blocked Streams Memory Exhaustion

Summary A memory exhaustion vulnerability in the Netty HTTP/3 codec allows the creation of an infinite number of blocked streams, which can cause OOM error. Details The vulnerability exists in io.netty.handler.codec.http3.QpackDecodershouldWaitForDynamicTableUpdates: If a client sends a header...

Netty HTTP/3 QPACK Blocked Streams Memory Exhaustion

Summary A memory exhaustion vulnerability in the Netty HTTP/3 codec allows the creation of an infinite number of blocked streams, which can cause OOM error. Details The vulnerability exists in io.netty.handler.codec.http3.QpackDecodershouldWaitForDynamicTableUpdates: If a client sends a header...

Allocation of Resources Without Limits or Throttling

Overview Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling in shouldWaitForDynamicTableUpdates in QpackDecoder. An attacker can open an indefinite number of persistently blocked streams by sending headers that reference dynamic table entries...

CVE-2026-48748 Netty HTTP/3 QPACK Blocked Streams Memory Exhaustion

Netty is a network application framework for development of protocol servers and clients. Starting in version 4.2.0.Final and prior to version 4.2.15.Final, a memory exhaustion vulnerability in the Netty HTTP/3 codec allows the creation of an infinite number of blocked streams, which can cause OO...