CVE-2023-28531
published 2023-03-17CVE-2023-28531: ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints. The earliest affected version is 8.9.
PriorityP348critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
2.22%
80.4th percentile
ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints. The earliest affected version is 8.9.
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | openssh | < openssh 1:9.2p1-2+deb12u2 (bookworm) | openssh 1:9.2p1-2+deb12u2 (bookworm) |
| msrc | cbl2_openssh_8.9p1-5_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_1.0_arm | — | — |
| msrc | cbl_mariner_1.0_x64 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
| msrc | cm1_openssh_8.9p1-2_on_cbl_mariner_1.0 | — | — |
| openbsd | openssh | >= 0 < 1:9.2p1-2+deb12u2 | 1:9.2p1-2+deb12u2 |
| openbsd | openssh | >= 0 < 1:9.3p1-1 | 1:9.3p1-1 |
| openbsd | openssh | >= 0 < 1:9.3p1-1 | 1:9.3p1-1 |
| openbsd | openssh | >= 0 < 1:8.2p1-4ubuntu0.10 | 1:8.2p1-4ubuntu0.10 |
| openbsd | openssh | >= 0 < 1:8.9p1-3ubuntu0.5 | 1:8.9p1-3ubuntu0.5 |
| openbsd | openssh | >= 8.9 < 9.3 | 9.3 |
| paloalto | prisma_sd | — | — |
CVSS provenance
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_msrc9.8CRITICAL
vendor_redhat9.8CRITICAL
vendor_ubuntu9.8CRITICAL
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OSV
openssh vulnerabilities
osv·2023-12-19·CVSS 9.8
CVE-2023-48795 [CRITICAL] openssh vulnerabilities
openssh vulnerabilities
Fabian Bäumer, Marcus Brinkmann, Jörg Schwenk discovered that the SSH
protocol was vulnerable to a prefix truncation attack. If a remote attacker
was able to intercept SSH communications, extension negotiation messages
could be truncated, possibly leading to certain algorithms and features
being downgraded. This issue is known as the Terrapin attack. This update
adds protocol extensions to mitigate this issue. (CVE-2023-48795)
Luci Stanescu discovered that OpenSSH incorrectly added destination
constraints when smartcard keys were added to ssh-agent, contrary to
expectations. This issue only affected Ubuntu 22.04 LTS, and Ubuntu 23.04.
(CVE-2023-28531)
GHSA
GHSA-j839-ff8c-f62x: ssh-add in OpenSSH before 9
ghsa_unreviewed·2023-03-17
CVE-2023-28531 [CRITICAL] GHSA-j839-ff8c-f62x: ssh-add in OpenSSH before 9
ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints.
OSV
CVE-2023-28531: ssh-add in OpenSSH before 9
osv·2023-03-17·CVSS 9.8
CVE-2023-28531 [CRITICAL] CVE-2023-28531: ssh-add in OpenSSH before 9
ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints. The earliest affected version is 8.9.
CISA ICS
Siemens SIMATIC S7-1500 CPU Family
cisa_ics·2025-06-12
Siemens SIMATIC S7-1500 CPU Family
ICS Advisory
##
Siemens SIMATIC S7-1500 CPU Family
Release DateJune 12, 2025
Alert CodeICSA-25-162-05
Related topics:
Industrial Control System Vulnerabilities, Industrial Control Systems
As of January 10, 2023, CISA will no longer be updating ICS security advisories for Siemens product vulnerabilities beyond the initial advisory. For the most up-to-date information on vulnerabilities in this advisory, please see Siemens' ProductCERT Security Advisories (CERT Services | Services | Siemens Global).
View CSAF
## 1. EXECUTIVE SUMMARY
- CVSS v4 8.7
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: Siemens
- Equipment: SIMATIC S7-1500 CPU family
- Vulnerabilities: Missing Encryption of Sensitive Data, Out-of-bounds Read, Use After Free, Stack-
Palo Alto
PAN-SA-2024-0003 Informational Bulletin: Impact of OSS CVEs in Prisma SD-WAN ION
vendor_paloalto·2024-04-05·CVSS 4.3
CVE-2007-2768 [MEDIUM] PAN-SA-2024-0003 Informational Bulletin: Impact of OSS CVEs in Prisma SD-WAN ION
PAN-SA-2024-0003 Informational Bulletin: Impact of OSS CVEs in Prisma SD-WAN ION
The Palo Alto Networks Product Security Assurance team has evaluated the following open source software (OSS) CVEs as they relate to Prisma SD-WAN ION. While Prisma SD-WAN ION may include the
CVEs: CVE-2007-2768, CVE-2016-10010, CVE-2016-10011, CVE-2016-10012, CVE-2016-20012, CVE-2016-8858, CVE-2019-6109, CVE-2019-6110, CVE-2019-6111, CVE-2020-12062, CVE-2021-41617, CVE-2022-4450, CVE-2023-0215, CVE-2023-0286, CVE-2023-28531, CVE-2023-38408, CVE-2023-51384, CVE-2023-51385, CVE-2023-51767
Affected products: Prisma SD
Ubuntu
OpenSSH vulnerabilities
vendor_ubuntu·2023-12-19·CVSS 9.8
CVE-2023-48795 [CRITICAL] OpenSSH vulnerabilities
Title: OpenSSH vulnerabilities
Summary: Several security issues were fixed in OpenSSH.
Fabian Bäumer, Marcus Brinkmann, Jörg Schwenk discovered that the SSH
protocol was vulnerable to a prefix truncation attack. If a remote attacker
was able to intercept SSH communications, extension negotiation messages
could be truncated, possibly leading to certain algorithms and features
being downgraded. This issue is known as the Terrapin attack. This update
adds protocol extensions to mitigate this issue. (CVE-2023-48795)
Luci Stanescu discovered that OpenSSH incorrectly added destination
constraints when smartcard keys were added to ssh-agent, contrary to
expectations. This issue only affected Ubuntu 22.04 LTS, and Ubuntu 23.04.
(CVE-2023-28531)
Instructions: In general, a standard system updat
BSD
FreeBSD-SA-23:05.openssh: ssh-add does not honor per-hop destination constraints
bsd_advisories·2023-06-21·CVSS 9.8
CVE-2023-28531 [CRITICAL] FreeBSD-SA-23:05.openssh: ssh-add does not honor per-hop destination constraints
FreeBSD-SA-23:05.openssh Security Advisory
The FreeBSD Project
Topic: ssh-add does not honor per-hop destination constraints
Category: contrib
Module: openssh
Announced: 2023-06-21
Credits: Luci Stanescu
Affects: FreeBSD 12.4
Corrected: 2023-06-05 16:04:15 UTC (stable/12, 12.4-STABLE)
2023-06-21 05:43:42 UTC (releng/12.4, 12.4-RELEASE-p3)
CVE Name: CVE-2023-28531
For general information regarding FreeBSD Security Advisories,
including descriptions of the fields above, security branches, and the
following sections, please visit .
I. Background
OpenSSH is an implementation of the SSH protocol suite, providing an
encrypted and authenticated transport for a variety of services, including
remote shell access.
II. Problem Description
When using ssh-add(1) to add smartcard keys to ssh-agen
Red Hat
openssh: smartcard keys to ssh-agent without the intended per-hop destination constraints.
vendor_redhat·2023-03-17·CVSS 9.8
CVE-2023-28531 [CRITICAL] openssh: smartcard keys to ssh-agent without the intended per-hop destination constraints.
openssh: smartcard keys to ssh-agent without the intended per-hop destination constraints.
ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints. The earliest affected version is 8.9.
A vulnerability was found in openssh. This issue occurs when adding smartcard keys to ssh-agent(1) with per-hop destination constraints. A logic error prevented the constraints from being communicated to the agent, resulting in the keys being added without constraints. The common cases of non-smartcard keys and keys without destination constraints are unaffected.
Package: openssh (Red Hat Enterprise Linux 6) - Not affected
Package: openssh (Red Hat Enterprise Linux 7) - Not affected
Package: openssh (Red Hat Enterprise Linux 8) - Not affected
Microsoft
ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints. The earliest affected version is 8.9.
vendor_msrc·2023-03-14·CVSS 9.8
CVE-2023-28531 [CRITICAL] ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints. The earliest affected version is 8.9.
ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints. The earliest affected version is 8.9.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
mitre
Debian
CVE-2023-28531: openssh - ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the inten...
vendor_debian·2023·CVSS 9.8
CVE-2023-28531 [CRITICAL] CVE-2023-28531: openssh - ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the inten...
ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints. The earliest affected version is 8.9.
Scope: local
bookworm: resolved (fixed in 1:9.2p1-2+deb12u2)
bullseye: resolved
forky: resolved (fixed in 1:9.3p1-1)
sid: resolved (fixed in 1:9.3p1-1)
trixie: resolved (fixed in 1:9.3p1-1)
No detection rules found.
No public exploits indexed.
Huntress
CVE-2023-28531 (OpenSSH Constraint Bypass) Vulnerability: Analysis, Impact, Mitigation | Huntress
blogs_huntress·CVSS 9.8
CVE-2023-28531 [CRITICAL] CVE-2023-28531 (OpenSSH Constraint Bypass) Vulnerability: Analysis, Impact, Mitigation | Huntress
CVE-2023-28531 Vulnerability
Published: 01/20/2026
Written by: Nadine Rozell
## What is CVE-2023-28531 vulnerability?
CVE-2023-28531 is a logic error vulnerability in the OpenSSH suite, specifically affecting the ssh-add utility.
## When was it discovered?
CVE-2023-28531 was publicly disclosed around March 16, 2023 . It was identified as a regression introduced in OpenSSH version 8.9 and was addressed in the release of OpenSSH 9.3 .
## Affected products & versions
The vulnerability affects specific versions of OpenSSH that support the per-hop destination constraint feature for smartcards.
Product
Versions Affected
Fixed Versions / Patch Links
OpenSSH
8.9 through 9.2
Upgrade to 9.3 or later
Ubuntu Linux
22.04 LTS, 22.10
Update openssh-client packages
Debian Linux
Bookworm
Bugzilla
CVE-2023-28531 openssh: smartcard keys to ssh-agent without the intended per-hop destination constraints.
bugzilla·2023-03-17·CVSS 9.8
CVE-2023-28531 [CRITICAL] CVE-2023-28531 openssh: smartcard keys to ssh-agent without the intended per-hop destination constraints.
CVE-2023-28531 openssh: smartcard keys to ssh-agent without the intended per-hop destination constraints.
ssh-add in OpenSSH before 9.3 adds smartcard keys to ssh-agent without the intended per-hop destination constraints.
https://www.openwall.com/lists/oss-security/2023/03/15/8
Discussion:
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):
https://access.redhat.com/security/cve/cve-2023-28531
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AN2UDTXEUSKFIOIYMV6JNI5VSBMYZOFT/https://security.gentoo.org/glsa/202307-01https://security.netapp.com/advisory/ntap-20230413-0008/https://www.debian.org/security/2023/dsa-5586https://www.openwall.com/lists/oss-security/2023/03/15/8https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/AN2UDTXEUSKFIOIYMV6JNI5VSBMYZOFT/https://lists.fedoraproject.org/archives/list/[email protected]/message/AN2UDTXEUSKFIOIYMV6JNI5VSBMYZOFT/https://security.gentoo.org/glsa/202307-01https://security.netapp.com/advisory/ntap-20230413-0008/https://www.debian.org/security/2023/dsa-5586https://www.openwall.com/lists/oss-security/2023/03/15/8https://cert-portal.siemens.com/productcert/html/ssa-082556.html
2023-03-17
Published