PT-2019-6236 · Libssh2+3 · Libssh2+3

Kevin Backhouse · Published 2019-03-28 · Updated 2023-09-08 · CVE-2019-13115

Positive Technologies (AI Summary)

CVSS v2.0

8.8

High

Base vector

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

Name of the Vulnerable Software and Affected Versions libssh2 versions prior to 1.9.0

Description The issue is related to an integer overflow in the kex method diffie hellman group exchange sha256 key exchange function of the kex.c component in the Libssh2 library, which implements the SSH2 protocol. This overflow could lead to an out-of-bounds read when 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.

Recommendations For versions prior to 1.9.0, update to version 1.9.0 or later to resolve the issue. As a temporary workaround, consider restricting access to SSH servers until the update is applied. Avoid using the kex method diffie hellman group exchange sha256 key exchange function in the affected libssh2 library until the issue is resolved.

Exploit

Fix

DoS

Integer Overflow

Out of bounds Read

Weakness Enumeration

CWE-190

CWE-125

Related Identifiers

ALT-PU-2019-2297

ALT-PU-2019-2369

BDU:2022-05873

CVE-2019-13115

DLA-1730-3

DLA-2848-1

DLA-3559-1

USN-5308-1

Affected Products

Alt Linux

Astra Linux

Ubuntu

Libssh2

References · 52

• 🔥 https://blog.semmle.com/libssh2-integer-overflow · Exploit
• 🔥❌ https://github.com/kevinbackhouse/SecurityExploits/tree/8cbdbbe6363510f7d9ceec685373da12e6fc752d/libssh2/out_of_bounds_read_disconnect_CVE-2019-17498 · Exploit, Deleted
• https://wiki.astralinux.ru/astra-linux-se47-bulletin-2024-0416SE47 · Vendor Advisory
• https://ubuntu.com/security/CVE-2019-17498 · Vendor Advisory
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/M7IF3LNHOA75O4WZWIHJLIRMA5LJUED3 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-5308-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2019-3856 · Vendor Advisory
• https://ubuntu.com/security/CVE-2019-3857 · Vendor Advisory
• https://osv.dev/vulnerability/ALPINE-CVE-2019-13115 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2019-13115 · Security Note
• https://bdu.fstec.ru/vul/2022-05873 · Security Note
• https://ubuntu.com/security/CVE-2019-13115 · Vendor Advisory
• https://ubuntu.com/security/CVE-2019-3862 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2019-13115 · Vendor Advisory
• https://ubuntu.com/security/CVE-2019-3859 · Vendor Advisory