Skip to content

The API function `ssh_get_hexa()` is vulnerable, when 0...

Moderate severity Unreviewed Published Mar 26, 2026 to the GitHub Advisory Database • Updated May 19, 2026

Package

No package listed— Suggest a package

Affected versions

Unknown

Patched versions

Unknown

Description

The API function ssh_get_hexa() is vulnerable, when 0-lenght
input is provided to this function. This function is used internally
in ssh_get_fingerprint_hash() and ssh_print_hexa() (deprecated),
which is vulnerable to the same input (length is provided by the
calling application).

The function is also used internally in the gssapi code for logging
the OIDs received by the server during GSSAPI authentication. This
could be triggered remotely, when the server allows GSSAPI authentication
and logging verbosity is set at least to SSH_LOG_PACKET (3). This
could cause self-DoS of the per-connection daemon process.

References

Published by the National Vulnerability Database Mar 26, 2026
Published to the GitHub Advisory Database Mar 26, 2026
Last updated May 19, 2026

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
Low

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L

EPSS score

Exploit Prediction Scoring System (EPSS)

This score estimates the probability of this vulnerability being exploited within the next 30 days. Data provided by FIRST.
(45th percentile)

Weaknesses

Buffer Underwrite ('Buffer Underflow')

The product writes to a buffer using an index or pointer that references a memory location prior to the beginning of the buffer. Learn more on MITRE.

CVE ID

CVE-2026-0966

GHSA ID

GHSA-wcqf-w94x-4wg2

Source code

No known source code

Dependabot alerts are not supported on this advisory because it does not have a package from a supported ecosystem with an affected and fixed version.

Learn more about GitHub language support

Loading Checking history
See something to contribute? Suggest improvements for this vulnerability.