PT-2026-63370

Name of the Vulnerable Software and Affected Versions NLnet Labs Unbound versions 1.22.0 through 1.25.1 Description A memory-accounting bypass exists in the downstream DNS-over-QUIC DoQ implementation. When DoQ is enabled, the first two bidirectional streams on a new QUIC connection stream id 0 a...

PT-2026-63367

Name of the Vulnerable Software and Affected Versions NLnet Labs Unbound versions 1.22.0 through 1.25.1 Description In DNS-over-QUIC DoQ environments, high concurrency and system pressure can trigger an assertion in the libngtcp2 library regarding monotonic timestamps. This occurs because Unbound...

unbound -- multiple vulnerabilities

NLnet Labs reports: This release consolidates security fixes for issues reported over a period of time. There are fixes for: CVE-2026-14586: Assertion in libngtcp2 when under pressure in high concurrency DNS-over-QUIC environments. CVE-2026-32665: Remote DNS-over-QUIC denial of service due to...

PT-2026-63391

Name of the Vulnerable Software and Affected Versions NLnet Labs Unbound versions 1.22.0 through 1.25.1 Description A remote unauthenticated client can terminate the entire resolver process using a single DNS-over-QUIC DoQ connection and one normal DNS query. This occurs when ngtcp2 conn writev...

PT-2026-63372

Name of the Vulnerable Software and Affected Versions NLnet Labs Unbound versions 1.22.0 through 1.25.1 Description Client terminated DNS-over-QUIC DoQ queries are not accounted for properly, leading to an inflation of the waiting number of replies for in-flight resolution queries. This causes a...

CVE-2026-56816

Netty HTTP/3 vulnerability (CVE-2026-56816): The Http3FrameCodec buffers incoming reserved HTTP/3 frame types up to the wire payload length and trusts payLoadLength, enabling an attacker to open many QUIC streams and send frames with oversized payloads, causing memory exhaustion and denial of ser...

CVE-2026-56816 Netty: Memory Exhaustion via HTTP/3 Reserved Frame Types

Netty is a network application framework for development of protocol servers and clients. Prior to 4.2.16.Final, Netty's Http3FrameCodec buffers incoming data for HTTP/3 reserved frame types up to the wire-specified payload length without limits; decodeFrame trusts payLoadLength, allowing an...

CVE-2026-16318

The QUIC transport parameters extension handler in s2n-tls incorrectly uses s2nalloc instead of s2nrealloc to store the peer's transport parameters. When a TLS 1.3 connection goes through a HelloRetryRequest, the handler is called twice on the same connection. On the second call, s2nalloc zeroes...

CVE-2026-16318

The CVE-2026-16318 issue affects server-side QUIC deployments using s2n-tls, where the QUIC transport parameters extension handler uses s2n_alloc instead of s2n_realloc. During TLS 1.3 HelloRetryRequest, the handler runs twice on the same connection; on the second run it zeroes the existing point...

CVE-2026-16318 QUIC Transport Parameters Memory Leak During HelloRetryRequest in s2n-tls

The QUIC transport parameters extension handler in s2n-tls incorrectly uses s2nalloc instead of s2nrealloc to store the peer's transport parameters. When a TLS 1.3 connection goes through a HelloRetryRequest, the handler is called twice on the same connection. On the second call, s2nalloc zeroes...

CVE-2026-16318 QUIC Transport Parameters Memory Leak During HelloRetryRequest in s2n-tls

The QUIC transport parameters extension handler in s2n-tls incorrectly uses s2nalloc instead of s2nrealloc to store the peer's transport parameters. When a TLS 1.3 connection goes through a HelloRetryRequest, the handler is called twice on the same connection. On the second call, s2nalloc zeroes...

EUVD-2026-46402

The QUIC transport parameters extension handler in s2n-tls incorrectly uses s2nalloc instead of s2nrealloc to store the peer's transport parameters. When a TLS 1.3 connection goes through a HelloRetryRequest, the handler is called twice on the same connection. On the second call, s2nalloc zeroes...

PT-2026-62072

Name of the Vulnerable Software and Affected Versions s2n-tls versions prior to v1.7.6 Description The QUIC transport parameters extension handler incorrectly uses s2n alloc instead of s2n realloc to store peer transport parameters. In TLS 1.3 connections involving a HelloRetryRequest, the handle...

CVE-2026-26081

HAProxy Community Edition 3.0 through 3.3 before 3.3.3 lacks a length check for the NEWTOKEN format. HAProxy Enterprise and ALOHA are also affected...

CVE-2026-26080

HAProxy Community Edition 3.2.x through 3.3.x before 3.3.3 can enter a loop or crash because varint is mishandled. HAProxy Enterprise and ALOHA are also affected...

CVE-2026-44435

Quicly is an IETF QUIC protocol implementation intended primarily for use within the H2O HTTP server. Prior to commit 937d0e9, an assertion failure is raised when the total number of valid handshake messages received over a CRYPTO stream of a single packet number space exceeds 32KB, causing a...

CVE-2026-44452

h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 8dc37cb, when h2o receives a ClientHello message over TLS or QUIC and it contains a zero-length SNI extension, the h2o server runs over the zero-length hostname while trying to copy the hostname, assuming that it ...

CVE-2026-44436

Quicly (QUIC implementation used with H2O) is vulnerable to a Denial of Service due to connection state corruption caused by a 255-byte Connection ID handling in the decoder, while QUIC version 1 requires a 20-byte CID buffer. The library lacked enforcement for 20-byte CIDs, allowing mismatched I...

CVE-2026-44436 Quicly is vulnerable to connection state corruption

Quicly is an IETF QUIC protocol implementation intended primarily for use within the H2O HTTP server. Prior to commit 8b178e6, Quicly is vulnerable to a Denial of Service attack through connection state corruption. In QUIC Invariants, the maximum length of a Connection ID is 255 bytes, while QUIC...

CVE-2026-44434 Quicly is vulnerable to stateless reset injection

Quicly is an IETF QUIC protocol implementation intended primarily for use within the H2O HTTP server. Prior to commit dccf5d4, Quicly was vulnerable to stateless reset injection through lack of packet entry validation. The QUIC protocol is designed to withstand packet injection attacks, once the...