CVE-2023-51767

OpenSSH through 10.0, when common types of DRAM are used, might allow row hammer attacks (for authentication bypass) because the integer value of authenticated in mm_answer_authpassword does not resist flips of a single bit. NOTE: this is applicable to a certain threat model of attacker-victim co-location in which the attacker has user privileges. NOTE: this is disputed by the Supplier, who states "we do not consider it to be the application's responsibility to defend against platform architectural weaknesses."

Published: 2023-12-24 Last update: 2026-06-02 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-51767 is rated Moderate Risk (45/100): CVSS High severity, with low exploitation likelihood (EPSS 0.66%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-51767

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.01% 0.66% +0.65%
2 2025-11-21 0.08% 0.01% -0.07%
3 2025-11-18 — 0.08% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-51767

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.0 3.1 HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.0 5.9 [email protected]
7.0 3.1 HIGH
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.0 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2023-51767

OS Trackers for CVE-2023-51767

vendor priority summary link
alpine — CVE-2023-51767: 1 source package rows (openssh); 78 state rows across 8 repos (3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, 3.23-main, edge-main); fixed 30, open 48. https://security.alpinelinux.org/vuln/CVE-2023-51767
redhat medium — https://access.redhat.com/security/cve/CVE-2023-51767
suse medium CVE-2023-51767 severity moderate: SUSE including 6 source package names (openssh, openssh-clients, openssh-common, openssh-fips, openssh-helpers, openssh-server), 147 product×package rows across 37 product lines (SUSE CaaS Platform 4.0, SUSE Enterprise Storage 7.1, … (37 product lines)): Will Not Fix 147. https://www.suse.com/security/cve/CVE-2023-51767/
ubuntu medium CVE-2023-51767 medium priority: Ubuntu including 2 source packages (openssh, openssh-ssh1), 16 status rows across 8 suites (bionic, focal, jammy, lunar, mantic, trusty, upstream, xenial): not-affected 10, ignored 3, DNE 2, needs-triage 1. https://ubuntu.com/security/CVE-2023-51767

Affected software / configurations for CVE-2023-51767

Vendor Product Version Raw CPE
openbsd openssh — cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*
fedoraproject fedora 39 cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux 9.0 cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*

References for CVE-2023-51767

URL Tags
https://access.redhat.com/security/cve/CVE-2023-51767 Third Party Advisory
https://arxiv.org/abs/2309.02545 Technical Description
https://bugzilla.redhat.com/show_bug.cgi?id=2255850 Issue Tracking Third Party Advisory
https://github.com/openssh/openssh-portable/blob/8241b9c0529228b4b86d88b1a6076fb9f97e4a99/auth-passwd.c#L77 Product
https://github.com/openssh/openssh-portable/blob/8241b9c0529228b4b86d88b1a6076fb9f97e4a99/monitor.c#L878 Product
https://security.netapp.com/advisory/ntap-20240125-0006/ Third Party Advisory
https://ubuntu.com/security/CVE-2023-51767 Third Party Advisory
https://www.openwall.com/lists/oss-security/2025/09/22/1
http://www.openwall.com/lists/oss-security/2025/09/22/1
http://www.openwall.com/lists/oss-security/2025/09/22/2
http://www.openwall.com/lists/oss-security/2025/09/23/1
http://www.openwall.com/lists/oss-security/2025/09/23/3
http://www.openwall.com/lists/oss-security/2025/09/23/4
http://www.openwall.com/lists/oss-security/2025/09/23/5
http://www.openwall.com/lists/oss-security/2025/09/24/4
http://www.openwall.com/lists/oss-security/2025/09/24/7
http://www.openwall.com/lists/oss-security/2025/09/25/2
http://www.openwall.com/lists/oss-security/2025/09/25/6
http://www.openwall.com/lists/oss-security/2025/09/26/2
http://www.openwall.com/lists/oss-security/2025/09/26/4
http://www.openwall.com/lists/oss-security/2025/09/27/1
http://www.openwall.com/lists/oss-security/2025/09/27/2
http://www.openwall.com/lists/oss-security/2025/09/27/3
http://www.openwall.com/lists/oss-security/2025/09/27/4
http://www.openwall.com/lists/oss-security/2025/09/27/5
http://www.openwall.com/lists/oss-security/2025/09/27/6
http://www.openwall.com/lists/oss-security/2025/09/27/7
http://www.openwall.com/lists/oss-security/2025/09/28/7
http://www.openwall.com/lists/oss-security/2025/09/29/1
http://www.openwall.com/lists/oss-security/2025/09/29/4
http://www.openwall.com/lists/oss-security/2025/09/29/5
http://www.openwall.com/lists/oss-security/2025/09/29/6
http://www.openwall.com/lists/oss-security/2025/10/01/1
http://www.openwall.com/lists/oss-security/2025/10/01/2
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