---
id: CVE-2026-59842
title: A flaw was found in libssh
summary: >-
  A flaw was found in libssh. During server-side GSSAPI key exchange, a
  client-supplied Curve25519 public key shorter than the expected length is
  copied without proper length validation, leading to an out-of-bounds heap
  read. This could al…
severity: low
cvss: 3.7
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N'
cwe:
  - CWE-125
vendor: libssh
product: libssh
affected:
  - libssh = 0.12.0
  - hardened_images
  - enterprise_linux = 10.0
  - enterprise_linux = 10.2
  - enterprise_linux_for_els = 10.2
  - enterprise_linux_for_eus = 10.2
  - enterprise_linux_for_ibm_z_systems = 10.0
  - enterprise_linux_for_ibm_z_systems = 10.2
  - enterprise_linux_for_ibm_z_systems_els = 10.2
  - enterprise_linux_for_ibm_z_systems_eus = 10.2
  - enterprise_linux_for_power_little_endian = 10.0
  - enterprise_linux_for_power_little_endian = 10.2
  - enterprise_linux_for_power_little_endian_els = 10.2
  - enterprise_linux_for_power_little_endian_eus = 10.2
published: '2026-07-21'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T19:47:55.080'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-59842'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2026:42922'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:55855'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-59842'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2498168'
    label: secalert@redhat.com
tags:
  - nvd
epss: 0.00493
epssPercentile: 0.39675
ingestedAt: '2026-09-22T20:10:15.030Z'
---

## Overview

A flaw was found in libssh. During server-side GSSAPI key exchange, a client-supplied Curve25519 public key shorter than the expected length is copied without proper length validation, leading to an out-of-bounds heap read. This could allow a remote unauthenticated attacker to disclose small amounts of server memory.

## Affected

- `libssh = 0.12.0`
- `hardened_images`
- `enterprise_linux = 10.0`
- `enterprise_linux = 10.2`
- `enterprise_linux_for_els = 10.2`
- `enterprise_linux_for_eus = 10.2`
- `enterprise_linux_for_ibm_z_systems = 10.0`
- `enterprise_linux_for_ibm_z_systems = 10.2`
- `enterprise_linux_for_ibm_z_systems_els = 10.2`
- `enterprise_linux_for_ibm_z_systems_eus = 10.2`
- `enterprise_linux_for_power_little_endian = 10.0`
- `enterprise_linux_for_power_little_endian = 10.2`
- `enterprise_linux_for_power_little_endian_els = 10.2`
- `enterprise_linux_for_power_little_endian_eus = 10.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.