Linux Distros Unpatched Vulnerability : CVE-2026-55199

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that...

CoreWCF: Pre-authentication infinite-loop CPU exhaustion in CoreWCF net.tcp / net.pipe / net.uds framing handshake

Impact An unauthenticated remote attacker can pin one server thread‑pool worker at 100 % CPU per connection. With a few connections, the CPU usage can be exhausted. Preconditions An attacker being able to reach a service which is exposing an endpoint using one of NetTcpBinding, NetNamedPipeBindin...

GHSA-P86G-XRR2-PF7C CoreWCF: Pre-authentication infinite-loop CPU exhaustion in CoreWCF net.tcp / net.pipe / net.uds framing handshake

Impact An unauthenticated remote attacker can pin one server thread‑pool worker at 100 % CPU per connection. With a few connections, the CPU usage can be exhausted. Preconditions An attacker being able to reach a service which is exposing an endpoint using one of NetTcpBinding, NetNamedPipeBindin...

SUSE CVE-2026-55199

libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can s...

ALPINE-CVE-2026-55199

libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can s...

CVE-2026-55199

libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can s...

CVE-2026-55199

libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can s...

UBUNTU-CVE-2026-55199

libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can s...

CVE-2026-55199 libssh2 - Pre-Authentication DoS via SSH_MSG_EXT_INFO Handler

libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can s...

EUVD-2026-37782

libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can s...

CVE-2026-55199 libssh2 - Pre-Authentication DoS via SSH_MSG_EXT_INFO Handler

libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can s...

CVE-2026-55199 libssh2 - Pre-Authentication DoS via SSH_MSG_EXT_INFO Handler

libssh2 through 1.11.1, fixed in commit 1762685, contains a pre-authentication denial of service vulnerability in the SSHMSGEXTINFO handler in src/packet.c that allows a malicious SSH server to cause a client CPU exhaustion loop by sending a crafted extension count value. A malicious server can s...

CVE-2026-55199

CVE-2026-55199 affects libssh2 up to version 1.11.1. The vulnerability lies in the SSH_MSG_EXT_INFO handler (src/packet.c), where return values from _libssh2_get_string() are unchecked. During key exchange, a malicious SSH server can set nr_extensions to 0xFFFFFFFF, causing the client to spin in ...

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...

PT-2026-50527

Name of the Vulnerable Software and Affected Versions libssh2 versions prior to 1.11.1 Description A pre-authentication denial of service issue exists in the SSH MSG EXT INFO handler within src/packet.c. A malicious SSH server can trigger a CPU exhaustion loop on the client by sending a crafted...

CVE-2026-9507

A session fixation vulnerability has been identified in osTicket v1.18.2. This security flaw allows an attacker to hijack a victim’s account by keeping the initial session identifier OSTSESSID active after a successful login. The issue lies in the fact that the application does not invalidate the...

BIT-PARSE-2026-47138 Parse Server: Pre-authentication denial of service via client version header regex backtracking

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.77 and 9.9.1, an unauthenticated attacker who knows a publicly-known Parse Application ID can submit a single HTTP request whose client SDK version field contains...

BIT-MONGODB-2026-9740 Unbounded recursion in BSONColumn interleaved-reference causes pre-auth stack overflow

A vulnerability in MongoDB Server's BSON validation logic allows an unauthenticated user to crash the mongod process by sending a specially crafted message. The BSON validator's handling of certain nested binary data structures permits uncontrolled mutual recursion between validation functions,...

EUVD-2026-37079

A session fixation vulnerability has been identified in osTicket v1.18.2. This security flaw allows an attacker to hijack a victim’s account by keeping the initial session identifier OSTSESSID active after a successful login. The issue lies in the fact that the application does not invalidate the...

CVE-2026-9507 Session fixation vulnerability in Enhancesoft's osTicket

A session fixation vulnerability has been identified in osTicket v1.18.2. This security flaw allows an attacker to hijack a victim’s account by keeping the initial session identifier OSTSESSID active after a successful login. The issue lies in the fact that the application does not invalidate the...