CVE-2020-1730: Null Pointer Dereference

Published Apr 13, 2020
·
Updated

A flaw was found in libssh versions before 0.8.9 and before 0.9.4 in the way it handled AES-CTR (or DES ciphers if enabled) ciphers. The server or client could crash when the connection hasn't been fully initialized and the system tries to cleanup the ciphers when closing the connection. The biggest threat from this vulnerability is system availability.

Affected Software

10 affected componentsFixes available
libssh libssh>=0.8.0<0.8.9
libssh libssh>=0.9.0<0.9.4
NetApp Cloud Backup
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=19.10
Fedoraproject Fedora=31
Fedoraproject Fedora=32
redhat Enterprise Linux=8.0
Oracle MySQL Workbench<=8.0.21
debian/libssh
0.9.8-0+deb11u10.9.8-0+deb11u20.10.6-0+deb12u20.10.6-0+deb12u10.11.2-1+deb13u10.11.3-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/libssh to a version that resolves this vulnerability.

    Fixed in 0.9.8-0+deb11u1Fixed in 0.9.8-0+deb11u2Fixed in 0.10.6-0+deb12u2Fixed in 0.10.6-0+deb12u1Fixed in 0.11.2-1+deb13u1Fixed in 0.11.3-1
  2. Upgrade

    Upgrade libssh to a version that resolves this vulnerability.

    Fixed in 0.8.9
  3. Upgrade

    Upgrade libssh to a version that resolves this vulnerability.

    Fixed in 0.9.4

Event History

Apr 13, 2020
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·07:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Feb 23, 2026
Data Sourced
via Ubuntu·08:49 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Debian·08:49 PM
DescriptionAffected Software
Data Sourced
via Launchpad·08:49 PM
Description

Frequently Asked Questions

1

What is CVE-2020-1730?

CVE-2020-1730 is a vulnerability in libssh versions before 0.8.9 and before 0.9.4 that could cause a crash when closing the connection.

2

How severe is CVE-2020-1730?

CVE-2020-1730 has a severity score of 5.3, which is considered medium severity.

3

Which software is affected by CVE-2020-1730?

CVE-2020-1730 affects libssh versions before 0.8.9 and before 0.9.4, as well as Netapp Cloud Backup, Canonical Ubuntu Linux 18.04 and 19.10, Fedora 31 and 32, Redhat Enterprise Linux 8.0, and Oracle Mysql Workbench 8.0.21.

4

How can I fix CVE-2020-1730?

To fix CVE-2020-1730, update libssh to version 0.8.9 or 0.9.4 if you are using it, and apply any available patches or updates for the affected software listed in the vulnerability description.

5

Where can I find more information about CVE-2020-1730?

You can find more information about CVE-2020-1730 in the references provided: [link 1], [link 2], [link 3].

Contact

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