CVE-2019-3859NVD

Vulnerability Summary

An out of bounds read flaw was discovered in libssh2 before 1.8.1 in the _libssh2_packet_require and _libssh2_packet_requirev functions. A remote attacker who compromises a SSH server may be able to cause a Denial of Service or read data in the client memory.

Severity Level

CRITICAL(9.1)

Published Date

Mar 21, 2019

Last Modified

Oct 14, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

6.28%Probability

Root Weakness (CWE)

CWE-125: Out-of-bounds Read ↗

The software reads data past the end, or before the beginning, of the intended buffer.

CVSS v3.1 Base Metrics — Score 9.1 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityNone

AvailabilityHigh

Affected & Patched Versions

Affected Versions

Libssh2 Libssh2 < 1.8.1
Fedoraproject Fedora
Debian Debian Linux
Netapp Ontap Select Deploy Administration Utility
Opensuse Leap

Patched Versions

Libssh2 Libssh2 1.8.1

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