CVE-2026-59248

Allocation of resources without limits vulnerability in ninenines cowlib allows an unauthenticated remote HTTP/2 or HTTP/3 peer to exhaust memory on the vulnerable server or client and cause a denial of service. The HPACK and QPACK prefixed-integer decoder cowhpackcommon:decbigint/3 in...

CVE-2026-59248 Unbounded HPACK/QPACK prefixed-integer decoding in Cowlib causes memory-exhaustion DoS

Allocation of resources without limits vulnerability in ninenines cowlib allows an unauthenticated remote HTTP/2 or HTTP/3 peer to exhaust memory on the vulnerable server or client and cause a denial of service. The HPACK and QPACK prefixed-integer decoder cowhpackcommon:decbigint/3 in...

CVE-2026-59248

CVE-2026-59248 affects cowlib (2.0.0–2.19.0). The HPACK/QPACK dec_big_int/3 decoder has no limit on continuation octets or resulting bit width, causing unbounded memory allocation during decoding and potential memory exhaustion DoS when handling untrusted HTTP/2/3 peers. A single maximal HPACK in...

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 an uncontrolled resource consumption. Exploiting this vulnerability could allow a malicious actor to cause service...

CVE-2026-12523

The CVE-2026-12523 issue affects Cloudflare’s quiche HTTP/3 implementation. The vulnerability stems from memory exhaustion due to how certain HTTP/3 frame types are parsed and memory is pre-allocated based on declared frame lengths, combined with improper QPACK decompression limits. Specifically,...

Linux Distros Unpatched Vulnerability : CVE-2026-55213

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - 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...

UBUNTU-CVE-2026-55213

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...

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...

CVE-2026-55213

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...

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...

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 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

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...