CVE-2026-58050

Name
CVE-2026-58050
Description
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.
NVD Severity
unknown
Other trackers
CVE, NVD, CERT, CVE Details, CIRCL, Arch Linux, Debian, Red Hat, Ubuntu, Gentoo, SUSE (Bugzilla), SUSE (CVE), Mageia
Mailing lists
oss-security, full-disclosure, bugtraq
Exploits
Exploit DB, Metasploit
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
disclosure@vulncheck.com https://github.com/bikini/exploitarium/tree/main/libssh2-publickey-list-calc-poc
disclosure@vulncheck.com https://github.com/libssh2/libssh2/blob/master/src/publickey.c
disclosure@vulncheck.com https://www.vulncheck.com/advisories/libssh2-integer-overflow-in-publickey-subsystem-attribute-allocation

Match rules

CPE URI Source package Min version Max version
cpe:2.3:a:libssh2:libssh2:*:*:*:*:*:*:*:* libssh2 >= None <= 1.11.1

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
libssh2 edge-main 1.11.1-r3 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 edge-main 1.11.1-r2 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 edge-main 1.11.1-r1 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 edge-main 1.11.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 edge-main 1.11.0-r1 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 edge-main 1.9.0-r2 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 edge-main 1.9.0-r1 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 edge-main 1.9.0-r0 None possibly vulnerable
libssh2 edge-main 1.8.1-r0 None possibly vulnerable
libssh2 3.24-main 1.11.1-r3 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.24-main 1.11.1-r2 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.23-main 1.11.1-r3 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.23-main 1.11.1-r2 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.23-main 1.11.1-r1 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.22-main 1.11.1-r2 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.22-main 1.11.1-r1 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.22-main 1.11.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.22-main 1.11.0-r1 None possibly vulnerable
libssh2 3.22-main 1.9.0-r1 None possibly vulnerable
libssh2 3.22-main 1.9.0-r0 None possibly vulnerable
libssh2 3.22-main 1.8.1-r0 None possibly vulnerable
libssh2 3.21-main 1.11.1-r2 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.21-main 1.11.1-r1 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.21-main 1.11.1-r0 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.21-main 1.11.0-r1 None possibly vulnerable
libssh2 3.21-main 1.9.0-r1 None possibly vulnerable
libssh2 3.21-main 1.9.0-r0 None possibly vulnerable
libssh2 3.21-main 1.8.1-r0 None possibly vulnerable
libssh2 3.20-main 1.11.0-r3 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.20-main 1.11.0-r2 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.20-main 1.11.0-r1 None possibly vulnerable
libssh2 3.20-main 1.9.0-r1 None possibly vulnerable
libssh2 3.20-main 1.9.0-r0 None possibly vulnerable
libssh2 3.20-main 1.8.1-r0 None possibly vulnerable
libssh2 3.19-main 1.11.0-r1 Natanael Copa <ncopa@alpinelinux.org> possibly vulnerable
libssh2 3.19-main 1.9.0-r1 None possibly vulnerable
libssh2 3.19-main 1.9.0-r0 None possibly vulnerable
libssh2 3.19-main 1.8.1-r0 None possibly vulnerable