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 num_attrs * sizeof(libssh2_publickey_attribute) without bounds checking, so on 32-bit platforms the multiplication overflows to an undersized buffer. A malicious SSH server can then drive the attribute-parsing loop to write past the allocation, causing a heap buffer overflow in a connecting libssh2 client.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/bikini/exploitarium/tree/main/libssh2-publickey-list-calc-poc	Broken Link
https://github.com/libssh2/libssh2/blob/master/src/publickey.c	Product
https://www.vulncheck.com/advisories/libssh2-integer-overflow-in-publickey-subsystem-attribute-allocation	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:libssh2:libssh2:*:*:*:*:*:*:*:*

History

30 Jun 2026, 20:27

Type	Values Removed	Values Added
CPE		cpe:2.3:a:libssh2:libssh2::::::::
First Time		Libssh2 libssh2 Libssh2
References	~~() https://github.com/bikini/exploitarium/tree/main/libssh2-publickey-list-calc-poc -~~	() https://github.com/bikini/exploitarium/tree/main/libssh2-publickey-list-calc-poc - Broken Link
References	~~() https://github.com/libssh2/libssh2/blob/master/src/publickey.c -~~	() https://github.com/libssh2/libssh2/blob/master/src/publickey.c - Product
References	~~() https://www.vulncheck.com/advisories/libssh2-integer-overflow-in-publickey-subsystem-attribute-allocation -~~	() https://www.vulncheck.com/advisories/libssh2-integer-overflow-in-publickey-subsystem-attribute-allocation - Third Party Advisory

28 Jun 2026, 02:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-28 02:16

Updated : 2026-06-30 20:27

NVD link : CVE-2026-58050

Mitre link : CVE-2026-58050

CVE.ORG link : CVE-2026-58050

JSON object : View

Products Affected

libssh2

libssh2

CWE

CWE-190

Integer Overflow or Wraparound

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