ESB-2018.0932.2 - UPDATE [Ubuntu] libssl1.0.0: Denial of service - Remote/unauthenticated 2018-04-20

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             AUSCERT External Security Bulletin Redistribution

                           OpenSSL vulnerability
                               20 April 2018


        AusCERT Security Bulletin Summary

Product:           libssl1.0.0
Publisher:         Ubuntu
Operating System:  Ubuntu
Impact/Access:     Denial of Service -- Remote/Unauthenticated
Resolution:        Patch/Upgrade
CVE Names:         CVE-2018-0739  

Reference:         ESB-2018.0896

Original Bulletin:

Revision History:  April 20 2018: Update to include Ubuntu 12.04 ESM
                   March 29 2018: Initial Release

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Ubuntu Security Notice USN-3611-2
April 17, 2018

openssl vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  o Ubuntu 12.04 ESM


Several security issues were fixed in OpenSSL.

Software Description

  o openssl - Secure Socket Layer (SSL) cryptographic library and tools


USN-3611-1 fixed a vulnerability in OpenSSL. This update provides the
corresponding update for Ubuntu 12.04 ESM.

Original advisory details:

It was discovered that OpenSSL incorrectly parsed the IPAddressFamily extension
in X.509 certificates, resulting in an erroneous display of the certificate in
text format. (CVE-2017-3735)

It was discovered that OpenSSL incorrectly handled certain ASN.1 types. A
remote attacker could possibly use this issue to cause a denial of service.

Update instructions

The problem can be corrected by updating your system to the following package

Ubuntu 12.04 ESM
    libssl1.0.0 - 1.0.1-4ubuntu5.40
    openssl - 1.0.1-4ubuntu5.40

To update your system, please follow these instructions: https://

After a standard system update you need to reboot your computer to make all the
necessary changes.


  o CVE-2017-3735
  o CVE-2018-0739

(C) 2017 Canonical Ltd. Ubuntu and Canonical are registered trademarks of
Canonical Ltd.

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