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.

References[email protected]/message/6LUNHPW64IGCASZ4JQ2J5KDXNZN53DWW/[email protected]/message/M7IF3LNHOA75O4WZWIHJLIRMA5LJUED3/


Source: MITRE

Published: 2019-07-16

Updated: 2020-08-24

Type: CWE-190

Risk Information

CVSS v2.0

Base Score: 5.8

Vector: AV:N/AC:M/Au:N/C:P/I:N/A:P

Impact Score: 4.9

Exploitability Score: 8.6

Severity: MEDIUM

CVSS v3.0

Base Score: 8.1

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H

Impact Score: 5.2

Exploitability Score: 2.8

Severity: HIGH