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Fencer Vulns
medium 5.5

CVE-2023-51384 json

In ssh-agent in OpenSSH before 9.6, certain destination constraints can be incompletely applied.

published 2023-12-18 2 y ago modified 2026-10-15 25 d ago also EUVD-2023-56105 , JLSEC-2026-69

cvss
5.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 37%
public exploits
0
none known

Summary

In ssh-agent in OpenSSH before 9.6, certain destination constraints can be incompletely applied. When destination constraints are specified during addition of PKCS#11-hosted private keys, these constraints are only applied to the first key, even if a PKCS#11 token returns multiple keys.

Patch / fix

  • julia OpenSSH_jll 9.9.1+0
  • Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem V1.1
  • openssh Debian 12 1:9.2p1-2+deb12u2
  • openssh Debian 14, Debian 13 1:9.6p1-1

debian advisories DEBIAN-CVE-2023-51384

  • openssh Ubuntu 22.04 LTS 1:8.9p1-3ubuntu0.6
  • openssh Ubuntu 24.04 LTS 1:9.6p1-3ubuntu1

ubuntu advisories UBUNTU-CVE-2023-51384

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • openssh Alpine 3.16 9.0_p1-r5
  • openssh Alpine 3.17 9.1_p1-r5
  • openssh Alpine 3.24, Alpine 3.23, Alpine 3.22 +3 more 9.6_p1-r0

alpine advisories ALPINE-CVE-2023-51384

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • openssh CBL-Mariner 2.0 8.9p1-3
  • openssh Azure Linux 3.0 9.7p1-1

azure linux advisories AZL-32205AZL-35081

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-26-295-11 updated cvss 5.5

Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.7 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.7 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.7
    affected: mitigation, no fix available

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-26-209-04 updated cvss 5.5

Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.6 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.6 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.6 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.6 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.6
    affected: mitigation, no fix available

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

red hat product security vex CVE-2023-51384 updated cvss 5.5

openssh: destination constraints only apply to first PKCS#11 key

  • Red Hat Enterprise Linux 6 openssh, openssh-ldap, openssh-server, openssh-askpass, openssh-clients, pam_ssh_agent_auth Red Hat Enterprise Linux 7 openssh, openssh-cavs, openssh-ldap, openssh-keycat, openssh-server, openssh-askpass, +3 more Red Hat Enterprise Linux 8 openssh, openssh-cavs, openssh-ldap, openssh-keycat, openssh-server, openssh-askpass, +2 more Red Hat Enterprise Linux 9 openssh, openssh-keycat, openssh-server, openssh-askpass, openssh-clients, pam_ssh_agent_auth
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-25-162-05 updated cvss 5.5

Siemens SIMATIC S7-1500 CPU family

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= 3.1.5 Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= 3.1.5 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= 3.1.5 Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) >= 3.1.5 Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) >= 3.1.5
    affected: mitigation, no fix available

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-25-044-09 updated cvss 5.5

Siemens SCALANCE W700 IEEE 802.11ax

  • Siemens SCALANCE WAB762-1 (6GK5762-1AJ00-6AA0) <V3.0.0 Siemens SCALANCE WAM763-1 (6GK5763-1AL00-7DA0) <V3.0.0 Siemens SCALANCE WAM763-1 (ME) (6GK5763-1AL00-7DC0) <V3.0.0 Siemens SCALANCE WAM763-1 (US) (6GK5763-1AL00-7DB0) <V3.0.0 Siemens SCALANCE WAM766-1 (6GK5766-1GE00-7DA0) <V3.0.0 Siemens SCALANCE WAM766-1 (ME) (6GK5766-1GE00-7DC0) <V3.0.0
    +13 more products
    Siemens SCALANCE WAM766-1 (US) (6GK5766-1GE00-7DB0) <V3.0.0 Siemens SCALANCE WAM766-1 EEC (6GK5766-1GE00-7TA0) <V3.0.0 Siemens SCALANCE WAM766-1 EEC (ME) (6GK5766-1GE00-7TC0) <V3.0.0 Siemens SCALANCE WAM766-1 EEC (US) (6GK5766-1GE00-7TB0) <V3.0.0 Siemens SCALANCE WUB762-1 (6GK5762-1AJ00-1AA0) <V3.0.0 Siemens SCALANCE WUB762-1 iFeatures (6GK5762-1AJ00-2AA0) <V3.0.0 Siemens SCALANCE WUM763-1 (6GK5763-1AL00-3AA0) <V3.0.0 Siemens SCALANCE WUM763-1 (6GK5763-1AL00-3DA0) <V3.0.0 Siemens SCALANCE WUM763-1 (US) (6GK5763-1AL00-3AB0) <V3.0.0 Siemens SCALANCE WUM763-1 (US) (6GK5763-1AL00-3DB0) <V3.0.0 Siemens SCALANCE WUM766-1 (6GK5766-1GE00-3DA0) <V3.0.0 Siemens SCALANCE WUM766-1 (ME) (6GK5766-1GE00-3DC0) <V3.0.0 Siemens SCALANCE WUM766-1 (USA) (6GK5766-1GE00-3DB0) <V3.0.0
    affected: fixed in V3.0.0 support.industry.siemens.com

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

cisa ICSA-23-166-11 updated cvss 5.5

Siemens SIMATIC S7-1500 TM MFP Linux Kernel

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CISA ADP 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CNA 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
OSV 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem package affected fixed in
julia OpenSSH_jll
>=8.9.0+0, <9.9.1+0
9.9.1+0

Affected products

  • Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP
  • Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP
  • Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
  • Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.