CVE-2026-66034 libssh2 Heap Out-of-Bounds Read via publickey subsystem

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2publickeylistfetch, the version 1...

EUVD-2026-48721

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2publickeylistfetch, the version 1...

CVE-2026-66034

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2publickeylistfetch, the version 1...

CVE-2026-66034: Out-of-bounds Read

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2publickeylistfetch, the version 1...

libssh2: Fix of CVE-2026-58050

CVE-2026-58050: cap publickey list attribute count to prevent 32-bit multiplication overflow in libssh2publickeylistfetch...

Updated libssh2 packages fix security vulnerabilities

The updated packages fix security vulnerabilities: Heap Buffer Over-read via sftpsymlink in sftp.c. CVE-2025-15661 libssh2 userauth.c userauthpassword integer overflow. CVE-2026-7598 Pre-Authentication DoS via SSHMSGEXTINFO Handler. CVE-2026-55199 Out-of-Bounds Write via Unchecked packetlength in...

MGASA-2026-0273 Updated libssh2 packages fix security vulnerabilities

The updated packages fix security vulnerabilities: Heap Buffer Over-read via sftpsymlink in sftp.c. CVE-2025-15661 libssh2 userauth.c userauthpassword integer overflow. CVE-2026-7598 Pre-Authentication DoS via SSHMSGEXTINFO Handler. CVE-2026-55199 Out-of-Bounds Write via Unchecked packetlength in...

Important: libssh2

Issue Overview: libssh2 through 1.11.1 reads an attacker-controlled 32-bit attribute count from a publickey-subsystem response and uses it in the allocation numattrs sizeoflibssh2publickeyattribute without bounds checking, so on 32-bit platforms the multiplication overflows to an undersized buffe...

Amazon Linux 2023 : libssh2, libssh2-devel (ALAS2023-2026-1966)

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-1966 advisory. libssh2 through 1.11.1 reads an attacker-controlled 32-bit attribute count from a publickey-subsystem response and uses it in the allocation numattrs sizeoflibssh2publickeyattribute without...

USN-8532-1: libssh2 vulnerabilities

It was discovered that libssh2 incorrectly handled certain publickey subsystem attributes. A remote attacker controlling a malicious SSH server could use this issue to cause a denial of service or possibly execute arbitrary code. CVE-2026-58050 It was discovered that libssh2 did not properly...

JLSEC-2026-663 libssh2 through 1.11.1 grows its publickey list with `SSH2_REALLOC` but does not zero-initialize new...

libssh2 through 1.11.1 grows its publickey list with SSH2REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2publickeylistfree operating on an uninitialized entry. A malicious SSH server offering the publickey...

JLSEC-2026-662 libssh2 through 1.11.1 reads an attacker-controlled 32-bit attribute count from a...

libssh2 through 1.11.1 reads an attacker-controlled 32-bit attribute count from a publickey-subsystem response and uses it in the allocation numattrs sizeoflibssh2publickeyattribute without bounds checking, so on 32-bit platforms the multiplication overflows to an undersized buffer. A malicious S...

TencentOS Server 4: libssh2 (TSSA-2026:0572)

The version of Tencent Linux installed on the remote TencentOS Server 4 host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the TSSA-2026:0572 advisory. Package updates are available for TencentOS Server 4 that fix the following vulnerabilities...

SUSE CVE-2026-58051

libssh2 through 1.11.1 grows its publickey list with SSH2REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2publickeylistfree operating on an uninitialized entry. A malicious SSH server offering the publickey...

libssh2 - Free of Uninitialized Pointer in publickey List Cleanup

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Integer Overflow or Wraparound

Overview Affected versions of this package are vulnerable to Integer Overflow or Wraparound through the processing of a 32-bit attribute count received from a remote server in the publickey subsystem. An attacker can cause a heap buffer overflow by sending a specially crafted response that trigge...

Use of Uninitialized Resource

Overview Affected versions of this package are vulnerable to Use of Uninitialized Resource in the cleanup process of the publickey list when a parse failure occurs. An attacker can cause memory corruption or a denial of service by sending a malformed response from a malicious SSH server that...

AZL-97395 CVE-2026-58051 affecting package rust for versions less than 1.75.0-30

libssh2 through 1.11.1 grows its publickey list with SSH2REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2publickeylistfree operating on an uninitialized entry. A malicious SSH server offering the publickey...

CVE-2026-58050

libssh2 through 1.11.1 reads an attacker-controlled 32-bit attribute count from a publickey-subsystem response and uses it in the allocation numattrs sizeoflibssh2publickeyattribute without bounds checking, so on 32-bit platforms the multiplication overflows to an undersized buffer. A malicious S...

CVE-2026-58051

libssh2 through 1.11.1 grows its publickey list with SSH2REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2publickeylistfree operating on an uninitialized entry. A malicious SSH server offering the publickey...