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CVE-2026-58050 (GCVE-0-2026-58050)

Vulnerability from cvelistv5 – Published: 2026-06-28 01:32 – Updated: 2026-06-29 12:27
VLAI
Title
libssh2 - Integer Overflow in publickey Subsystem Attribute Allocation
Summary
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.
Severity
7 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
8.3 (High)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-29 12:26 UTC
CWE
  • CWE-190 - Integer Overflow or Wraparound
Assigner
References
Impacted products
Vendor Product Version CPE status
libssh2 libssh2 Affected: 0 , ≤ 1.11.1 (semver)
    cpe:2.3:a:libssh2:libssh2:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-06-25 00:00
Credits
ashdfrkl
Show details on NVD website
To clipboard 

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