crypto/tls: golang: Go crypto/tls: Denial of Service via multiple TLS 1.3 key update messages

A flaw was found in the crypto/tls package within the Go golang standard library, specifically affecting TLS 1.3 connections. A remote attacker can exploit this vulnerability by sending multiple key update messages in a single record after the handshake. This can cause the connection to deadlock,...

CVE-2026-55199

A vulnerability in libssh2 allows a malicious SSH server to freeze connected clients during the handshake process. By sending a malformed packet, the server triggers a loop that exhausts the client's CPU, resulting in a denial of service. Mitigation To mitigate this issue, ensure your libssh2...

CVE-2026-53622

CVE-2026-53622 concerns Traefik’s HTTP/3 (QUIC) TLS configuration selection. When HTTP/3 is enabled, the TLS handshake uses an exact, case-sensitive lookup of the SNI to choose a TLS config, which fails to match wildcard hosts or mixed-case hostnames. If a router enforces mTLS via TLSOptions and ...

CVE-2026-48491 Traefik: SNICheck ignores wildcard TLSOptions mappings, allowing domain-fronted mTLS bypass

Traefik is an HTTP reverse proxy and load balancer. From 3.7.0 until 3.7.3, there is a high severity vulnerability in Traefik's domain-fronting protection SNICheck that allows an unauthenticated client to bypass mutual TLS enforced through wildcard router TLSOptions. When a router uses a wildcard...

CVE-2026-55517

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.5, a Deno program that opens a client WebSocket connection could be crashed by the remote server. While handling the WebSocket handshake response, Deno parsed the Sec-WebSocket-Protocol and Sec-WebSocket-Extensions response...

CVE-2026-55517

CVE-2026-55517 affects Deno prior to 2.7.5, where a client WebSocket handshake could crash the process if the server returned non-ASCII bytes in Sec-WebSocket-Protocol or Sec-WebSocket-Extensions headers. The root cause is parsing those headers as ASCII strings, triggering a panic when non-printa...

Gogs has Unauthenticated Asymmetric Denial of Service (DoS) via SSH Handshake Stall (File Descriptor Exhaustion)

The Gogs built-in Go SSH server is vulnerable to an unauthenticated, asymmetric Denial of Service DoS attack. The application accepts inbound TCP connections and passes them to golang.org/x/crypto/ssh.NewServerConn inside a new goroutine without enforcing any read/write deadlines on the underlyin...

GHSA-XP79-5MX3-JX52 Gogs has Unauthenticated Asymmetric Denial of Service (DoS) via SSH Handshake Stall (File Descriptor Exhaustion)

The Gogs built-in Go SSH server is vulnerable to an unauthenticated, asymmetric Denial of Service DoS attack. The application accepts inbound TCP connections and passes them to golang.org/x/crypto/ssh.NewServerConn inside a new goroutine without enforcing any read/write deadlines on the underlyin...

JLSEC-2026-622 Predictable WebSocket masking key and handshake nonce in HTTP.jl client

Description The WebSocket client masking key wssendframe! and the Sec-WebSocket-Key handshake nonce wsrandomhandshakekey were generated with randUInt8, n, which draws from the task-local Xoshiro256++ PRNG. Xoshiro is not cryptographically secure: its internal state can be recovered from a short r...

PT-2026-51632

Name of the Vulnerable Software and Affected Versions Gogs versions prior to 0.14.3 Description The built-in Go SSH server in Gogs is subject to an unauthenticated, asymmetric Denial of Service DoS attack. The application accepts inbound TCP connections and passes them to the ssh.NewServerConn...

Astra Linux – Vulnerability in Thunderbird

If Thunderbird was configured to use STARTTLS for an IMAP connection, and an attacker injected IMAP server responses before the STARTTLS handshake was completed, then Thunderbird did not ignore the injected data. This could result in Thunderbird displaying incorrect information. For example, the...

Astra Linux - Vulnerability in Golang-1.19

Extremely large RSA keys in certificate chains can cause clients and servers to spend significant CPU time verifying signatures. With this fix, the size of RSA keys transmitted during handshake operations is limited to 8192 bits or less. Based on a survey of publicly trusted RSA keys, there are...

Astra Linux – Vulnerability in mbedtls

A issue was discovered in Mbed TLS 3.5.1. There is a persistent handshake denial if a client sends a TLS 1.3 ClientHello without extensions...

Astra Linux – Vulnerabilities in Firefox, Thunderbird, NSS

An unchecked return value in the TLS handshake code could have caused a potentially exploitable crash. This vulnerability affects Firefox 122, Firefox ESR 115.9, and Thunderbird 115.9...

Astra Linux – Vulnerability in Linux 5.10

In the Linux kernel, the following vulnerability has been resolved: net/handshake: Fix handshakereqdestroytest1 Recently, the handshakereqdestroytest1 test started failing: The expected value of handshakereqdestroytest should be req, but the actual value is 0000000000000000. The correct value...

Astra Linux – Vulnerability in gnutls28

A issue was discovered in GnuTLS before version 3.6.15. A server can cause a NULL pointer dereferencing in a TLS 1.3 client if a norenegotiation alert is sent at an unexpected time, resulting in an invalid second handshake. The crash occurs during the application’s error handling process, where t...

netty-handler: Netty: Denial of Service due to eager buffer allocation in TLS handshake

A flaw was found in Netty, a network application framework. A remote attacker can exploit this vulnerability by sending a crafted TLS Transport Layer Security ClientHello message. This can lead to an eager allocation of a large memory buffer, causing a Denial of Service DoS due to excessive memor...

Deno: Denial of service via non-ASCII bytes in WebSocket response headers

Summary A Deno program that opens a client WebSocket connection could be crashed by the remote server. While handling the WebSocket handshake response, Deno parsed the Sec-WebSocket-Protocol and Sec-WebSocket-Extensions response headers in a way that assumed their bytes were always printable ASCI...

Unchecked Input for Loop Condition

Overview Affected versions of this package are vulnerable to Unchecked Input for Loop Condition in the SSHMSGEXTINFO handler during the initial handshake process. An attacker can cause the client application to become unresponsive by sending a crafted extension count value that triggers an infini...

eclipse-vertx/vert.x: eclipse-vertx/vert.x: Denial of Service via TLS handshake with wildcard server name

A flaw was found in eclipse-vertx/vert.x. A remote attacker can exploit this vulnerability by performing a Transport Layer Security TLS handshake and presenting a server name extension with a server wildcard name. This can lead to a denial of service DoS condition, impacting the availability of t...