libssh2: libssh2: Information disclosure and denial of service via crafted SFTP response

A flaw in libssh2's sftpsymlink function allows a malicious SSH server or man-in-the-middle attacker to trigger an out-of-bounds heap read via a crafted SSHFXPNAME response. This can disclose heap memory contents or crash the application, causing a denial of service DoS...

[SECURITY] [DSA 6365-1] libssh2 security update

------------------------------------------------------------------------- Debian Security Advisory DSA-6365-1 [email protected] https://www.debian.org/security/ Moritz Muehlenhoff June 25, 2026 https://www.debian.org/security/faq -...

libssh2: libssh2 - Out-of-Bounds Write via Unchecked packet_length in transport.c

An out-of-bounds write vulnerability exists in the libssh2 client. A remote attacker can exploit this by sending a specially crafted SSH packet with an abnormally large length value. This corrupts the application's memory and can potentially allow the attacker to execute arbitrary code on the...

libssh2: libssh2: Denial of Service via crafted SSH_MSG_EXT_INFO message

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...

Moderate: Red Hat Security Advisory: Red Hat Hardened Images RPMs bug fix and enhancement update

An update for Red Hat Hardened Images RPMs is now available. This update includes the following RPMs: libssh2: libssh2-1.11.1-8.hum1 aarch64, x8664 libssh2-devel-1.11.1-8.hum1 aarch64, x8664 libssh2-docs-1.11.1-8.hum1 noarch libssh2-1.11.1-8.hum1.src src...

OPENSUSE-SU-2026:21057-1 Security update for libssh2_org

This update for libssh2org fixes the following issues - CVE-2026-55199: pre-Authentication DoS via SSHMSGEXTINFO Handler bsc1268530. - CVE-2026-55200: out-of-Bounds write via Unchecked packetlength in transport.c bsc1268531...

SUSE-SU-2026:22284-1 Security update for libssh2_org

This update for libssh2org fixes the following issues - CVE-2026-55199: pre-Authentication DoS via SSHMSGEXTINFO Handler bsc1268530. - CVE-2026-55200: out-of-Bounds write via Unchecked packetlength in transport.c bsc1268531...

The vulnerabilities in libssh2 are addressed through libssh.

LibSSH has vulnerabilities in libssh2, including versions up to 1.11.1. The first vulnerability involves a denial-of-service attack during the pre-authentication phase, within the SSHMSGEXTINFO handler. A malicious SSH server can send a specially constructed extensioncount value, causing the clie...

The vulnerability of the ssh2_transport_read() function in the libssh2 library, which allows a hacker to execute arbitrary code.

The vulnerability of the ssh2transportread function in the libssh2 library is related to buffer overflows due to integer overflows. Exploiting this vulnerability could allow a remote attacker to execute arbitrary code using specially crafted SSH packets...

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-2026-55200

An out-of-bounds write vulnerability exists in the libssh2 client. A remote attacker can exploit this by sending a specially crafted SSH packet with an abnormally large length value. This corrupts the application's memory and can potentially allow the attacker to execute arbitrary code on the...

SUSE CVE-2025-15661

libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftpsymlink function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSHFXPNAME response...

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...

Linux Distros Unpatched Vulnerability : CVE-2025-15661

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 2dae302, contains an out-of-bounds heap read vulnerability in the sftpsymlink function in src/sftp.c that allows a...

Linux Distros Unpatched Vulnerability : CVE-2026-55200

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 7acf3df contains an out-of-bounds write vulnerability in ssh2transportread that fails to enforce upper bounds on...

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...

SUSE CVE-2026-55200

libssh2 through 1.11.1, fixed in commit 7acf3df contains an out-of-bounds write vulnerability in ssh2transportread that fails to enforce upper bounds on packetlength field. Remote attackers can send crafted SSH packets with excessively large packetlength values to corrupt heap memory and achieve...

CVE-2025-15661

libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftpsymlink function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSHFXPNAME response...

ALPINE-CVE-2025-15661

libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftpsymlink function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSHFXPNAME response...

AZL-90936 CVE-2025-15661 affecting package libssh2 for versions less than 1.11.1-4

libssh2 through 1.11.1, fixed in commit 2dae302, contains an out-of-bounds heap read vulnerability in the sftpsymlink function in src/sftp.c that allows a malicious SSH server or man-in-the-middle attacker to disclose heap memory contents or cause a crash by sending a crafted SSHFXPNAME response...