In libssh2 before 1.9.0, kex_method_diffie_hellman_group_exchange_sha256_key_exchange in kex.c has an integer overflow that could lead to an out-of-bounds read in the way packets are read from the server. A remote attacker who compromises a SSH server may be able to disclose sensitive information or cause a denial of service condition on the client system when a user connects to the server. This is related to an _libssh2_check_length mistake, and is different from the various issues fixed in 1.8.1, such as CVE-2019-3855.
CVSS Details
- CVSS 3.1 Base Score: 8.1
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Alpine Linux | alpine-linux-upgrade-libssh2 | Nov 8, 2019 | Jul 16, 2019 | |
| Debian | debian-upgrade-libssh2 | Jul 29, 2019 | Jul 16, 2019 | |
| Oracle Solaris | oracle-solaris-11-4-upgrade-library-libssh2-1-9-0-11-4-21-0-1-69-0 | Jan 19, 2021 | Jul 16, 2019 | |
| Redhat_linux | — | no-fix-redhat-rpm-package | Jul 9, 2025 | Jul 16, 2019 |
| Ubuntu | ubuntu-pro-upgrade-libssh2-1 | Mar 22, 2023 | Jul 16, 2019 | |
| Vmware Photon_os | vmware-photon_os_update_tdnf | Jan 20, 2025 | Jul 16, 2019 |
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