CVE-2019-3855: Integer Overflow

Published Mar 11, 2019
·
Updated

A malicious server could send a specially crafted packet which could result in an unchecked integer overflow. The value would then be used to allocate memory causing a possible memory write out of bounds error.

Other sources

An integer overflow flaw which could lead to an out of bounds write was discovered in libssh2 before 1.8.1 in the way packets are read from the server. A remote attacker who compromises a SSH server may be able to execute code on the client system when a user connects to the server.

IDE SCM. Multiple issues were addressed by updating to version 2.16.

Credit

Chris Coulson

Affected Software

22 affected componentsFixes available
debian/libssh2<=1.8.0-2, <=1.4.3-4.1+deb8u1, <=1.4.3-1, <=1.7.0-1
1.4.3-4.1+deb8u21.8.0-2.11.7.0-1+deb9u1
debian/libssh2
1.8.0-2.11.8.0-2.1+deb10u11.9.0-21.10.0-31.11.0-2
redhat/libssh2<1.8.1
1.8.1
Apple Xcode<11.0
11.0
libssh2 libssh2<1.8.1
Fedoraproject Fedora=28
Fedoraproject Fedora=29
Fedoraproject Fedora=30
Debian Debian Linux=8.0
Debian Debian Linux=9.0
NetApp ONTAP Select Deploy administration utility
redhat Enterprise Linux=8.0
redhat Enterprise Linux Desktop=7.0
redhat Enterprise Linux Server=7.0
redhat Enterprise Linux Server Aus=7.6
redhat Enterprise Linux Server Eus=7.6
redhat Enterprise Linux Server Tus=7.6
redhat Enterprise Linux Workstation=7.0
openSUSE Leap=42.3
Apple Xcode<11.0
Oracle PeopleSoft Enterprise PeopleTools=8.56
Oracle PeopleSoft Enterprise PeopleTools=8.57

Event History

Mar 21, 2019
CVE Published
via MITRE·08:13 PM
Data Sourced
via MITRE·08:13 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·09:29 PM
RemedyDescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is CVE-2019-3855?

CVE-2019-3855 is an integer overflow flaw in libssh2 before version 1.8.1.

2

How severe is CVE-2019-3855?

CVE-2019-3855 has a severity rating of 8.8, which is classified as critical.

3

What is the impact of CVE-2019-3855?

CVE-2019-3855 could lead to an out-of-bounds write and allow a remote attacker to execute code when a user connects to a compromised SSH server.

4

Which software versions are affected by CVE-2019-3855?

The affected software includes libssh2 versions before 1.8.1, Xcode before version 11.0, and various versions of Debian, Fedora, Redhat, and other products.

5

How can I fix CVE-2019-3855?

To fix CVE-2019-3855, update libssh2 to version 1.8.1 or later, and ensure you are using the latest versions of other affected software.

Contact

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