DEBIAN-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...

MGASA-2026-0179 Updated golang-x-crypto & golang-x-sys-devel packages fix security vulnerability

fixes a protocol weakness in the golang.org/x/crypto/ssh package that allowed a MITM attacker to compromise the integrity of the secure channel before it was established, allowing them to prevent transmission of a number of messages immediately after the secure channel was established without...

USN-7108-2 python-asyncssh vulnerabilities

USN-7108-1 fixed vulnerabilities in AysncSSH. This update provides the corresponding update for Ubuntu 18.04 LTS. Original advisory details: Fabian Bäumer, Marcus Brinkmann, and Jörg Schwenk discovered that AsyncSSH did not properly handle the extension info message. An attacker able to intercept...

CVE-2023-46445

An issue in AsyncSSH before 2.14.1 allows attackers to control the extension info message RFC 8308 via a man-in-the-middle attack, aka a "Rogue Extension Negotiation."...

PYSEC-2023-237

An issue in AsyncSSH v2.14.0 and earlier allows attackers to control the extension info message RFC 8308 via a man-in-the-middle attack...

UBUNTU-CVE-2023-46445

An issue in AsyncSSH before 2.14.1 allows attackers to control the extension info message RFC 8308 via a man-in-the-middle attack, aka a "Rogue Extension Negotiation."...

CVE-2023-46445

An issue in AsyncSSH before 2.14.1 allows attackers to control the extension info message RFC 8308 via a man-in-the-middle attack, aka a "Rogue Extension Negotiation."...

CVE-2023-46445

An issue in AsyncSSH before 2.14.1 allows attackers to control the extension info message RFC 8308 via a man-in-the-middle attack, aka a "Rogue Extension Negotiation."...

AsyncSSH Rogue Extension Negotiation

Summary An issue in AsyncSSH v2.14.0 and earlier allows attackers to control the extension info message RFC 8308 via a man-in-the-middle attack. Details The rogue extension negotiation attack targets an AsyncSSH client connecting to any SSH server sending an extension info message. The attack...

GHSA-CFC2-WR2V-GXM5 AsyncSSH Rogue Extension Negotiation

Summary An issue in AsyncSSH v2.14.0 and earlier allows attackers to control the extension info message RFC 8308 via a man-in-the-middle attack. Details The rogue extension negotiation attack targets an AsyncSSH client connecting to any SSH server sending an extension info message. The attack...

PT-2023-9800 · Asyncssh +3 · Asyncssh +3

Name of the Vulnerable Software and Affected Versions: AsyncSSH versions prior to 2.14.1 Description: The issue in AsyncSSH allows attackers to control the extension info message via a man-in-the-middle attack, enabling them to conduct algorithm downgrade attacks during user authentication. This...