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...

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...

Photon OS 5.0: Libssh2 PHSA-2026-5.0-0857

An update of the libssh2 package has been released. %NASLMINLEVEL 80900 C Tenable, Inc. The descriptive text and package checks in this plugin were extracted from VMware Security Advisory PHSA-2026-5.0-0857. The text itself is copyright C VMware, Inc. include'compat.inc'; if description...

PT-2026-50528

Name of the Vulnerable Software and Affected Versions libssh2 versions prior to 1.11.2 Description An out-of-bounds write issue exists in the ssh2 transport read function due to an integer overflow and a failure to enforce upper bounds on the packet length field. A remote attacker operating a...

GHSA-JHP3-H4HP-2C3P vulnerabilities

Vulnerabilities for packages: libssh2...

CVE-2026-7598 vulnerabilities

Vulnerabilities for packages: libssh2...

GHSA-JHP3-H4HP-2C3P vulnerabilities

Vulnerabilities for packages: libssh2...

CVE-2026-7598 vulnerabilities

Vulnerabilities for packages: libssh2...

Medium: libssh2

Issue Overview: A security vulnerability has been detected in libssh2 up to 1.11.1. The impacted element is the function userauthpassword of the file src/userauth.c. Such manipulation of the argument usernamelen/passwordlen leads to integer overflow. The attack may be launched remotely. The name ...

Medium: libssh2

Issue Overview: A security vulnerability has been detected in libssh2 up to 1.11.1. The impacted element is the function userauthpassword of the file src/userauth.c. Such manipulation of the argument usernamelen/passwordlen leads to integer overflow. The attack may be launched remotely. The name ...

Amazon Linux 2023 : libssh2, libssh2-devel (ALAS2023-2026-1779)

It is, therefore, affected by a vulnerability as referenced in the ALAS2023-2026-1779 advisory. A security vulnerability has been detected in libssh2 up to 1.11.1. The impacted element is the function userauthpassword of the file src/userauth.c. Such manipulation of the argument...

Amazon Linux 2 : libssh2, --advisory ALAS2-2026-3329 (ALAS-2026-3329)

The version of libssh2 installed on the remote host is prior to 1.4.3-12. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2026-3329 advisory. A security vulnerability has been detected in libssh2 up to 1.11.1. The impacted element is the function userauthpassword of the...

[SECURITY] Fedora 43 Update: libssh2-1.11.1-6.fc43

libssh2 is a library implementing the SSH2 protocol as defined by Internet Drafts: SECSH-TRANS22, SECSH-USERAUTH25, SECSH-CONNECTION23, SECSH-ARCH20, SECSH-FILEXFER06, SECSH-DHGEX04, and SECSH-NUMBERS10...

Fedora 43 : libssh2 (2026-1b9134cdc9)

The remote Fedora 43 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-1b9134cdc9 advisory. This update addresses CVE-2026-7598, a potential heap buffer overflow, which could be triggered remotely by supplying very long username and/or password...

[SECURITY] Fedora 44 Update: libssh2-1.11.1-6.fc44

libssh2 is a library implementing the SSH2 protocol as defined by Internet Drafts: SECSH-TRANS22, SECSH-USERAUTH25, SECSH-CONNECTION23, SECSH-ARCH20, SECSH-FILEXFER06, SECSH-DHGEX04, and SECSH-NUMBERS10...

Fedora 44 : libssh2 (2026-f87ac8187c)

The remote Fedora 44 host has a package installed that is affected by a vulnerability as referenced in the FEDORA-2026-f87ac8187c advisory. This update addresses CVE-2026-7598, a potential heap buffer overflow, which could be triggered remotely by supplying very long username and/or password...

Ubuntu 24.04 LTS / 25.10 / 26.04 LTS : libssh2 vulnerability (USN-8309-1)

The remote Ubuntu 24.04 LTS / 25.10 / 26.04 LTS host has packages installed that are affected by a vulnerability as referenced in the USN-8309-1 advisory. It was discovered that libssh2 incorrectly handled username and password length values during SSH password authentication. A remote attacker...

Critical Photon OS Security Update - PHSA-2026-5.0-0857

Updates of 'rubygem-nokogiri', 'grub2', 'linux', 'glibc', 'nginx', 'libssh2', 'linux-esx', 'strongswan' packages of Photon OS have been released...

USN-8309-1: libssh2 vulnerability

It was discovered that libssh2 incorrectly handled username and password length values during SSH password authentication. A remote attacker could possibly use this issue to cause a denial of service...

Astra Linux – Vulnerability in libgit2

libgit2 is a cross-platform, linkable library implementation of Git. When using an SSH remote with the optional libssh2 backend, libgit2 does not perform certificate checking by default. Previous versions of libgit2 required the caller to set the certificatecheck field of the libgit2’s...