CVE-2026-58051 (GCVE-0-2026-58051)

Vulnerability from cvelistv5 – Published: 2026-06-28 01:32 – Updated: 2026-06-29 12:50
VLAI
Title
libssh2 - Free of Uninitialized Pointer in publickey List Cleanup
Summary
libssh2 through 1.11.1 grows its publickey list with SSH2_REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2_publickey_list_free operating on an uninitialized entry. A malicious SSH server offering the publickey subsystem can use a malformed response to make cleanup free an uninitialized, attacker-influenceable attrs pointer in a connecting libssh2 client.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H
8.3 (High)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-29 12:49 UTC
CWE
  • CWE-908 - Use of Uninitialized Resource
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7140 records in the last 180 days details
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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