CVE-2026-58051

Publication date 28 June 2026

Last updated 29 June 2026


Ubuntu priority

Cvss 3 Severity Score

6.5 · Medium

Score breakdown

Description

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.

Status

Package Ubuntu Release Status
libssh2 26.04 LTS resolute
Needs evaluation
25.10 questing
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
14.04 LTS trusty
Needs evaluation

Severity score breakdown

CVSS version:

Base score 8.3 · High

Vector: 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

Base score 6.5 · Medium

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H


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