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Vulnerability details: VCID-yy8r-ywzy-4kag
Vulnerability ID VCID-yy8r-ywzy-4kag
Aliases CVE-2018-15473
Summary OpenSSH through 7.7 is prone to a user enumeration vulnerability due to not delaying bailout for an invalid authenticating user until after the packet containing the request has been fully parsed, related to auth2-gss.c, auth2-hostbased.c, and auth2-pubkey.c.
Status Published
Exploitability 2.0
Weighted Severity 6.2
Risk 10.0
Affected and Fixed Packages Package Details
Weaknesses (2)
CWE-200 Exposure of Sensitive Information to an Unauthorized Actor
CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
System Score Found at
cvssv3 5.3 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2018-15473.json
epss 0.92345 https://api.first.org/data/v1/epss?cve=CVE-2018-15473
epss 0.92345 https://api.first.org/data/v1/epss?cve=CVE-2018-15473
epss 0.92468 https://api.first.org/data/v1/epss?cve=CVE-2018-15473
epss 0.92468 https://api.first.org/data/v1/epss?cve=CVE-2018-15473
epss 0.92468 https://api.first.org/data/v1/epss?cve=CVE-2018-15473
epss 0.92468 https://api.first.org/data/v1/epss?cve=CVE-2018-15473
epss 0.92648 https://api.first.org/data/v1/epss?cve=CVE-2018-15473
epss 0.92648 https://api.first.org/data/v1/epss?cve=CVE-2018-15473
cvssv3.1 5.3 https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
cvssv2 5.0 https://nvd.nist.gov/vuln/detail/CVE-2018-15473
cvssv3.1 5.3 https://nvd.nist.gov/vuln/detail/CVE-2018-15473
archlinux Medium https://security.archlinux.org/AVG-763
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2018-15473.json
https://api.first.org/data/v1/epss?cve=CVE-2018-15473
https://bugs.debian.org/906236
https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-15473
https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
https://github.com/openbsd/src/commit/779974d35b4859c07bc3cb8a12c74b43b0a7d1e0
https://lists.debian.org/debian-lts-announce/2018/08/msg00022.html
https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2018-0011
https://security.gentoo.org/glsa/201810-03
https://security.netapp.com/advisory/ntap-20181101-0001/
https://www.debian.org/security/2018/dsa-4280
https://www.exploit-db.com/exploits/45210/
https://www.exploit-db.com/exploits/45233/
https://www.exploit-db.com/exploits/45939/
https://www.oracle.com/security-alerts/cpujan2020.html
http://www.openwall.com/lists/oss-security/2018/08/15/5
http://www.securityfocus.com/bid/105140
http://www.securitytracker.com/id/1041487
1619063 https://bugzilla.redhat.com/show_bug.cgi?id=1619063
906236 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=906236
AVG-763 https://security.archlinux.org/AVG-763
cpe:2.3:a:netapp:aff_baseboard_management_controller:-:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netapp:aff_baseboard_management_controller:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:data_ontap_edge:-:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netapp:data_ontap_edge:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:fas_baseboard_management_controller:-:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netapp:fas_baseboard_management_controller:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:oncommand_unified_manager:*:*:*:*:*:vsphere:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netapp:oncommand_unified_manager:*:*:*:*:*:vsphere:*:*
cpe:2.3:a:netapp:ontap_select_deploy:-:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netapp:ontap_select_deploy:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:service_processor:-:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netapp:service_processor:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:virtual_storage_console:*:*:*:*:*:vsphere:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:netapp:virtual_storage_console:*:*:*:*:*:vsphere:*:*
cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*
cpe:2.3:a:oracle:sun_zfs_storage_appliance_kit:8.8.6:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:oracle:sun_zfs_storage_appliance_kit:8.8.6:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:netapp:clustered_data_ontap:-:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:netapp:clustered_data_ontap:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:data_ontap:-:*:*:*:*:7-mode:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:netapp:data_ontap:-:*:*:*:*:7-mode:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
CVE-2018-15473 Exploit https://bugfuzz.com/stuff/ssh-check-username.py
CVE-2018-15473 Exploit https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/linux/remote/45210.py
CVE-2018-15473 Exploit https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/linux/remote/45233.py
CVE-2018-15473 Exploit https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/linux/remote/45939.py
CVE-2018-15473 https://nvd.nist.gov/vuln/detail/CVE-2018-15473
RHSA-2019:0711 https://access.redhat.com/errata/RHSA-2019:0711
RHSA-2019:2143 https://access.redhat.com/errata/RHSA-2019:2143
USN-3809-1 https://usn.ubuntu.com/3809-1/
Data source Exploit-DB
Date added Dec. 4, 2018
Description OpenSSH < 7.7 - User Enumeration (2)
Ransomware campaign use Unknown
Source publication date Dec. 4, 2018
Exploit type remote
Platform linux
Source update date Dec. 4, 2018
Data source Metasploit
Description This module uses a malformed packet or timing attack to enumerate users on an OpenSSH server. The default action sends a malformed (corrupted) SSH_MSG_USERAUTH_REQUEST packet using public key authentication (must be enabled) to enumerate users. On some versions of OpenSSH under some configurations, OpenSSH will return a "permission denied" error for an invalid user faster than for a valid user, creating an opportunity for a timing attack to enumerate users. Testing note: invalid users were logged, while valid users were not. YMMV.
Note 
Stability:
  - crash-service-down
Reliability: []
SideEffects:
  - ioc-in-logs
  - account-lockouts
Ransomware campaign use Unknown
Source URL https://github.com/rapid7/metasploit-framework/tree/master/modules/auxiliary/scanner/ssh/ssh_enumusers.rb
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2018-15473.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Found at https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: AV:N/AC:L/Au:N/C:P/I:N/A:N Found at https://nvd.nist.gov/vuln/detail/CVE-2018-15473
Exploitability (E) Access Vector (AV) Access Complexity (AC) Authentication (Au) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

high

functional

unproven

proof_of_concept

not_defined

local

adjacent_network

network

high

medium

low

multiple

single

none

none

partial

complete

none

partial

complete

none

partial

complete
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Found at https://nvd.nist.gov/vuln/detail/CVE-2018-15473
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Exploit Prediction Scoring System (EPSS)
Percentile 0.99722
EPSS Score 0.92345
Published At Aug. 1, 2025, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2025-07-31T08:29:01.576633+00:00 Alpine Linux Importer Import https://secdb.alpinelinux.org/v3.14/main.json 37.0.0