CVE-2019-13115

HIGH

libssh2 < 1.9.0 - Integer Overflow leading to Out-of-Bounds Read in SSH Key Exchange

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 2 public exploits for CVE-2019-13115. PoCs published by viz27, CSSProject.

AI-analyzed exploit summary This repository provides a technical writeup and setup instructions for exploiting CVE-2019-13115, an out-of-bounds read vulnerability in libssh2. It includes steps to configure a malicious SSH server and verify the crash but lacks functional exploit code.

Description

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.

Exploits (2)

nomisec WRITEUP 1 stars
by viz27 · poc
https://github.com/viz27/Libssh2-Exploit

This repository provides a technical writeup and setup instructions for exploiting CVE-2019-13115, an out-of-bounds read vulnerability in libssh2. It includes steps to configure a malicious SSH server and verify the crash but lacks functional exploit code.

Classification
Writeup 80%
Attack Type
Info Leak
Complexity
Moderate
Reliability
Theoretical
Target: libssh2 1.8.2
No auth needed
Prerequisites: OpenSSH server setup · libssh2 1.8.2 compilation
devstral-2 · analyzed Feb 18, 2026 Full analysis →
nomisec STUB
by CSSProject · poc
https://github.com/CSSProject/libssh2-Exploit

The repository contains only a README with goals for developing an exploit for CVE-2019-13115 but no actual exploit code or technical details. It outlines a plan to create a malicious server to trigger crashes or retrieve data from libssh2 clients but lacks implementation.

Classification
Stub 90%
Attack Type
Other
Complexity
Theoretical
Reliability
Theoretical
Target: libssh2 (versions affected by CVE-2019-13115)
No auth needed
Prerequisites: OpenSSH server setup · libssh2 client connectivity
devstral-2 · analyzed Feb 18, 2026 Full analysis →

References (15)

Core 15
Core References
Mailing List, Third Party Advisory mailing-list
https://lists.debian.org/debian-lts-announce/2019/07/msg00024.html
Mailing List, Third Party Advisory mailing-list
https://lists.debian.org/debian-lts-announce/2021/12/msg00013.html
Issue Tracking, Third Party Advisory
https://github.com/libssh2/libssh2/pull/350
Release Notes, Vendor Advisory
https://libssh2.org/changes.html

Scores

CVSS v3 8.1
EPSS 0.1166
EPSS Percentile 95.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H

Details

CWE
CWE-125 CWE-190
Status published
Products (9)
debian/debian_linux 8.0
debian/debian_linux 9.0
f5/traffix_systems_signaling_delivery_controller 5.0.0 - 5.1.0
fedoraproject/fedora 29
fedoraproject/fedora 30
libssh2/libssh2 < 1.9.0
netapp/cloud_backup
netapp/e-series_santricity_os_controller 11.0.0 - 11.70.1
netapp/ontap_select_deploy_administration_utility
Published Jul 16, 2019
Tracked Since Feb 18, 2026