---
id: CVE-2020-14145
title: >-
  The client side in OpenSSH 5.7 through 8.4 has an Observable Discrepancy
  leading to an information leak in the algorithm negotiation
summary: >-
  The client side in OpenSSH 5.7 through 8.4 has an Observable Discrepancy
  leading to an information leak in the algorithm negotiation. This allows
  man-in-the-middle attackers to target initial connection attempts (where no
  host key for th…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-203
  - CWE-203
vendor: openbsd
product: openssh
affected:
  - 'openssh >= 5.7, < 8.4'
  - openssh = 8.4
  - openssh = 8.5
  - openssh = 8.6
  - aff_a700s_firmware
  - active_iq_unified_manager >= 9.5
  - hci_management_node
  - ontap_select_deploy_administration_utility
  - solidfire
  - steelstore_cloud_integrated_storage
  - hci_compute_node
  - hci_storage_node
patched:
  - openssh 8.4
published: '2020-06-29'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T10:17:29.537'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2020-14145'
references:
  - url: 'http://www.openwall.com/lists/oss-security/2020/12/02/1'
    label: cve@mitre.org
  - url: >-
      https://anongit.mindrot.org/openssh.git/commit/?id=b3855ff053f5078ec3d3c653cdaedefaa5fc362d
    label: cve@mitre.org
  - url: 'https://docs.ssh-mitm.at/CVE-2020-14145.html'
    label: cve@mitre.org
  - url: 'https://github.com/openssh/openssh-portable/compare/V_8_3_P1...V_8_4_P1'
    label: cve@mitre.org
  - url: >-
      https://github.com/ssh-mitm/ssh-mitm/blob/master/ssh_proxy_server/plugins/session/cve202014145.py
    label: cve@mitre.org
  - url: 'https://security.gentoo.org/glsa/202105-35'
    label: cve@mitre.org
  - url: 'https://security.netapp.com/advisory/ntap-20200709-0004/'
    label: cve@mitre.org
  - url: >-
      https://www.fzi.de/en/news/news/detail-en/artikel/fsa-2020-2-ausnutzung-eines-informationslecks-fuer-gezielte-mitm-angriffe-auf-ssh-clients/
    label: cve@mitre.org
  - url: 'http://www.openwall.com/lists/oss-security/2020/12/02/1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://anongit.mindrot.org/openssh.git/commit/?id=b3855ff053f5078ec3d3c653cdaedefaa5fc362d
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://docs.ssh-mitm.at/CVE-2020-14145.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/openssh/openssh-portable/compare/V_8_3_P1...V_8_4_P1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://github.com/ssh-mitm/ssh-mitm/blob/master/ssh_proxy_server/plugins/session/cve202014145.py
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.gentoo.org/glsa/202105-35'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.netapp.com/advisory/ntap-20200709-0004/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.fzi.de/en/news/news/detail-en/artikel/fsa-2020-2-ausnutzung-eines-informationslecks-fuer-gezielte-mitm-angriffe-auf-ssh-clients/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-398330.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
epss: 0.02057
epssPercentile: 0.80793
ingestedAt: '2026-10-14T10:25:41.178Z'
---

## Overview

The client side in OpenSSH 5.7 through 8.4 has an Observable Discrepancy leading to an information leak in the algorithm negotiation. This allows man-in-the-middle attackers to target initial connection attempts (where no host key for the server has been cached by the client). NOTE: some reports state that 8.5 and 8.6 are also affected.

## Affected

- `openssh >= 5.7, < 8.4`
- `openssh = 8.4`
- `openssh = 8.5`
- `openssh = 8.6`
- `aff_a700s_firmware`
- `active_iq_unified_manager >= 9.5`
- `hci_management_node`
- `ontap_select_deploy_administration_utility`
- `solidfire`
- `steelstore_cloud_integrated_storage`
- `hci_compute_node`
- `hci_storage_node`

## Remediation

Upgrade past the affected range:

- `openssh 8.4`