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NVD / CVE Program· CNA mitre

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…

Noroxi assessment

Priority: Monitor (action score 28/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.66% (FIRST EPSS); higher than 51.9% of all records.
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. Special conditions such as timing or configuration are required.
  • Fixed version: openssh (Alpine:v3.19) 9.7_p1-r0.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to openssh (Alpine:v3.19) 9.7_p1-r0 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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."

HighCVSS 7.0 · v3.1—No exploit Fix available
Published
Dec 24, 2023
Updated
Oct 15, 2026
EPSS
0.6% · 51th percentile
CWE
—

Report tools

JSON

Action score

28

Monitor

Low priority for now.

CVSS
28 / 40 · 7.0 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.6%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
7.0
CNA · mitre
7.0
agree

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2023-51767

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
openbsdopenssh
fedoraprojectfedora
redhatenterprise linux

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Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • fedoraproject fedora39
  • openbsd opensshall versions
  • redhat enterprise linux8.0
  • redhat enterprise linux9.0

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Alpine:v3.19opensshbefore 9.7_p1-r09.7_p1-r0

Same product

openbsd: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-123158sshd in OpenSSH before 10.6p2 on Linux, when musl libc is used without PAM, lacks a workaround for a password authentication bypass…KEV
    67This week
  • CVE-2023-38408The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently trustworthy search path, leading to remote code execution if…
    63This week
  • CVE-2018-15473OpenSSH through 7.7 is prone to a user enumeration vulnerability due to not delaying bailout for an invalid authenticating user until after…
    60This week

Published before and after this one in the same product

  • ← EarlierCVE-2023-51384Dec 18, 2023 · In ssh-agent in OpenSSH before 9.6, certain destination constraints can be incompletely applied.
    22Monitor
  • ← EarlierCVE-2023-51385Dec 18, 2023 · In ssh in OpenSSH before 9.6, OS command injection might occur if a user name or host name has shell metacharacters, and this name is…
    32Monitor
  • Later →CVE-2025-26465Feb 18, 2025 · Openssh: machine-in-the-middle attack if verifyhostkeydns is enabled
    29Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
alpine:openssh9.7_p1-r0 · Alpine:v3.19Package registry (OSV)
red hat:openssh0:10.3p1-2.hum1 · Red Hat:hummingbird:1Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • Special conditions such as timing or configuration are required.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
High
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

—

CVSS vector

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (19 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records