---
id: CVE-2024-6387
title: >-
  A security regression (CVE-2006-5051) was discovered in OpenSSH's server
  (sshd)
summary: >-
  A security regression (CVE-2006-5051) was discovered in OpenSSH's server
  (sshd). There is a race condition which can lead sshd to handle some signals
  in an unsafe manner. An unauthenticated, remote attacker may be able to
  trigger it by f…
severity: high
cvss: 8.1
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-364
  - CWE-362
vendor: openbsd
product: openssh
affected:
  - sma_6200_firmware
  - sma_7200_firmware
  - 'eos >= 4.32.0, <= 4.32.1f'
  - ubuntu_linux = 23.10
  - ubuntu_linux = 24.04
  - almalinux = 9.0
  - sma_6210_firmware
  - sma_7210_firmware
  - sma_8200v_firmware
  - sra_ex_7000_firmware
  - a1k_firmware
  - a70_firmware
  - a90_firmware
  - a700s_firmware
  - 8300_firmware
  - 8700_firmware
  - a400_firmware
  - c400_firmware
  - a250_firmware
  - 500f_firmware
  - c250_firmware
  - a800_firmware
  - c800_firmware
  - a900_firmware
  - a9500_firmware
  - c190_firmware
  - a150_firmware
  - a220_firmware
  - fas2720_firmware
  - fas2750_firmware
  - fas2820_firmware
  - bootstrap_os
  - 'macos >= 12.0, < 12.7.6'
  - 'macos >= 13.0, < 13.6.8'
  - 'macos >= 14.0, < 14.6'
  - openssh < 4.4
  - 'openssh >= 8.6, <= 9.8'
  - openssh = 4.4
  - openssh = 8.5
  - openssh = 8.6
  - openshift_container_platform = 4.0
  - enterprise_linux = 9.0
  - enterprise_linux_eus = 9.4
  - enterprise_linux_for_arm_64 = 9.0_aarch64
  - enterprise_linux_for_arm_64_eus = 9.4_aarch64
  - enterprise_linux_for_ibm_z_systems = 9.0_s390x
  - enterprise_linux_for_ibm_z_systems_eus = 9.4_s390x
  - enterprise_linux_for_power_little_endian = 9.0_ppc64le
  - enterprise_linux_for_power_little_endian_eus = 9.4_ppc64le
  - enterprise_linux_server_aus = 9.4
  - linux_enterprise_micro = 6.0
  - debian_linux = 12.0
  - ubuntu_linux = 22.04
  - ubuntu_linux = 22.10
  - ubuntu_linux = 23.04
  - amazon_linux = 2023.0
  - active_iq_unified_manager
  - 'e-series_santricity_os_controller >= 11.0.0, <= 11.70.2'
  - ontap = 9
  - ontap_select_deploy_administration_utility
  - ontap_tools = 9
  - ontap_tools = 10
  - freebsd = 13.2
  - freebsd = 13.3
  - freebsd = 14.0
  - freebsd = 14.1
  - netbsd <= 10.0.0
patched:
  - macos 14.6
  - openssh 4.4
published: '2024-07-01'
updated: '2026-08-31'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2024-6387'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2024:4312'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2024:4340'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2024:4389'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2024:4469'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2024:4474'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2024:4479'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/errata/RHSA-2024:4484'
    label: secalert@redhat.com
  - url: 'https://access.redhat.com/security/cve/CVE-2024-6387'
    label: secalert@redhat.com
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2294604'
    label: secalert@redhat.com
  - url: 'https://santandersecurityresearch.github.io/blog/sshing_the_masses.html'
    label: secalert@redhat.com
  - url: 'https://www.openssh.com/txt/release-9.8'
    label: secalert@redhat.com
  - url: 'https://www.qualys.com/2024/07/01/cve-2024-6387/regresshion.txt'
    label: secalert@redhat.com
  - url: 'http://seclists.org/fulldisclosure/2024/Jul/18'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://seclists.org/fulldisclosure/2024/Jul/19'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://seclists.org/fulldisclosure/2024/Jul/20'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/01/12'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/01/13'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/02/1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/03/1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/03/11'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/03/2'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/03/3'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/03/4'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/03/5'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/04/1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/04/2'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/08/2'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/08/3'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/09/2'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/09/5'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/10/1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/10/2'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/10/3'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/10/4'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/10/6'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/11/1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/11/3'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/23/4'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/23/6'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/28/2'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'http://www.openwall.com/lists/oss-security/2024/07/28/3'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/errata/RHSA-2024:4312'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/errata/RHSA-2024:4340'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/errata/RHSA-2024:4389'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/errata/RHSA-2024:4469'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/errata/RHSA-2024:4474'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/errata/RHSA-2024:4479'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/errata/RHSA-2024:4484'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://access.redhat.com/security/cve/CVE-2024-6387'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://archlinux.org/news/the-sshd-service-needs-to-be-restarted-after-upgrading-to-openssh-98p1/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://arstechnica.com/security/2024/07/regresshion-vulnerability-in-openssh-gives-attackers-root-on-linux/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://blog.qualys.com/vulnerabilities-threat-research/2024/07/01/regresshion-remote-unauthenticated-code-execution-vulnerability-in-openssh-server
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2294604'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://explore.alas.aws.amazon.com/CVE-2024-6387.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://forum.vmssoftware.com/viewtopic.php?f=8&t=9132'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://ftp.netbsd.org/pub/NetBSD/security/advisories/NetBSD-SA2024-002.txt.asc
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/AlmaLinux/updates/issues/629'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/Azure/AKS/issues/4379'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/PowerShell/Win32-OpenSSH/discussions/2248'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/PowerShell/Win32-OpenSSH/issues/2249'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/microsoft/azurelinux/issues/9555'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://github.com/openela-main/openssh/commit/e1f438970e5a337a17070a637c1b9e19697cad09
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/oracle/oracle-linux/issues/149'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/rapier1/hpn-ssh/issues/87'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://github.com/zgzhang/cve-2024-6387-poc'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://lists.almalinux.org/archives/list/announce@lists.almalinux.org/thread/23BF5BMGFVEVUI2WNVAGMLKT557EU7VY/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://lists.mindrot.org/pipermail/openssh-unix-announce/2024-July/000158.html
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://lists.mindrot.org/pipermail/openssh-unix-dev/2024-July/041431.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://news.ycombinator.com/item?id=40843778'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://packetstorm.news/files/id/190587/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2024-0010'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://santandersecurityresearch.github.io/blog/sshing_the_masses.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security-tracker.debian.org/tracker/CVE-2024-6387'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.netapp.com/advisory/ntap-20240701-0001/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://sig-security.rocky.page/issues/CVE-2024-6387/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://stackdiary.com/openssh-race-condition-in-sshd-allows-remote-code-execution/
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://support.apple.com/kb/HT214118'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://support.apple.com/kb/HT214119'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://support.apple.com/kb/HT214120'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://ubuntu.com/security/CVE-2024-6387'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://ubuntu.com/security/notices/USN-6859-1'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.akamai.com/blog/security-research/2024-openssh-vulnerability-regression-what-to-know-and-do
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.arista.com/en/support/advisories-notices/security-advisory/19904-security-advisory-0100
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.exploit-db.com/exploits/52269'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.freebsd.org/security/advisories/FreeBSD-SA-24:04.openssh.asc'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.openssh.com/txt/release-9.8'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.qualys.com/2024/07/01/cve-2024-6387/regresshion.txt'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.splunk.com/en_us/blog/security/cve-2024-6387-regresshion-vulnerability.html
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.suse.com/security/cve/CVE-2024-6387.html'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://www.theregister.com/2024/07/01/regresshion_openssh/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: >-
      https://www.vicarius.io/vsociety/posts/regresshion-an-openssh-regression-error-cve-2024-6387
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-082556.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-446545.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - exploit-available
epss: 0.99506
epssPercentile: 0.99944
exploitAvailable: true
ingestedAt: '2026-08-31T18:12:23.665Z'
exploits:
  exploitdb: true
  github: 96
  githubRepos:
    - 'https://github.com/7etsuo/cve-2024-6387-poc'
    - 'https://github.com/zgzhang/cve-2024-6387-poc'
    - 'https://github.com/acrono/cve-2024-6387-poc'
  checkedAt: '2026-09-20T17:26:50.179Z'
---

## Overview

A security regression (CVE-2006-5051) was discovered in OpenSSH's server (sshd). There is a race condition which can lead sshd to handle some signals in an unsafe manner. An unauthenticated, remote attacker may be able to trigger it by failing to authenticate within a set time period.

## Affected

- `sma_6200_firmware`
- `sma_7200_firmware`
- `eos >= 4.32.0, <= 4.32.1f`
- `ubuntu_linux = 23.10`
- `ubuntu_linux = 24.04`
- `almalinux = 9.0`
- `sma_6210_firmware`
- `sma_7210_firmware`
- `sma_8200v_firmware`
- `sra_ex_7000_firmware`
- `a1k_firmware`
- `a70_firmware`
- `a90_firmware`
- `a700s_firmware`
- `8300_firmware`
- `8700_firmware`
- `a400_firmware`
- `c400_firmware`
- `a250_firmware`
- `500f_firmware`
- `c250_firmware`
- `a800_firmware`
- `c800_firmware`
- `a900_firmware`
- `a9500_firmware`
- `c190_firmware`
- `a150_firmware`
- `a220_firmware`
- `fas2720_firmware`
- `fas2750_firmware`
- `fas2820_firmware`
- `bootstrap_os`
- `macos >= 12.0, < 12.7.6`
- `macos >= 13.0, < 13.6.8`
- `macos >= 14.0, < 14.6`
- `openssh < 4.4`
- `openssh >= 8.6, <= 9.8`
- `openssh = 4.4`
- `openssh = 8.5`
- `openssh = 8.6`
- `openshift_container_platform = 4.0`
- `enterprise_linux = 9.0`
- `enterprise_linux_eus = 9.4`
- `enterprise_linux_for_arm_64 = 9.0_aarch64`
- `enterprise_linux_for_arm_64_eus = 9.4_aarch64`
- `enterprise_linux_for_ibm_z_systems = 9.0_s390x`
- `enterprise_linux_for_ibm_z_systems_eus = 9.4_s390x`
- `enterprise_linux_for_power_little_endian = 9.0_ppc64le`
- `enterprise_linux_for_power_little_endian_eus = 9.4_ppc64le`
- `enterprise_linux_server_aus = 9.4`
- `linux_enterprise_micro = 6.0`
- `debian_linux = 12.0`
- `ubuntu_linux = 22.04`
- `ubuntu_linux = 22.10`
- `ubuntu_linux = 23.04`
- `amazon_linux = 2023.0`
- `active_iq_unified_manager`
- `e-series_santricity_os_controller >= 11.0.0, <= 11.70.2`
- `ontap = 9`
- `ontap_select_deploy_administration_utility`
- `ontap_tools = 9`
- `ontap_tools = 10`
- `freebsd = 13.2`
- `freebsd = 13.3`
- `freebsd = 14.0`
- `freebsd = 14.1`
- `netbsd <= 10.0.0`

## Remediation

Upgrade past the affected range:

- `macos 14.6`
- `openssh 4.4`