CVE-2026-59842

A flaw was found in libssh. During server-side GSSAPI key exchange, a client-supplied Curve25519 public key shorter than the expected length is copied without proper length validation, leading to an out-of-bounds heap read. This could allow a remote unauthenticated attacker to disclose small amounts of server memory.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/errata/RHSA-2026:42922	Vendor Advisory
https://access.redhat.com/errata/RHSA-2026:55855
https://access.redhat.com/security/cve/CVE-2026-59842	Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2498168	Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:libssh:libssh:-:::::::*
	cpe:2.3:a:redhat:hardened_images:-:::::::*
	cpe:2.3:o:redhat:enterprise_linux:10.0:::::::*

History

No history.

Information

Published : 2026-07-21 12:18

Updated : 2026-08-19 05:17

NVD link : CVE-2026-59842

Mitre link : CVE-2026-59842

CVE.ORG link : CVE-2026-59842

JSON object : View

Products Affected

redhat

enterprise_linux
hardened_images

libssh

libssh

CWE

CWE-125

Out-of-bounds Read

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