[USN-3937-2] Apache vulnerabilities

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Ubuntu Security Notice USN-3937-2
April 10, 2019

apache2 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 12.04 ESM

Summary:

Several security issues were fixed in Apache.

Software Description:
- apache2: Apache HTTP server

Details:

USN-3937-1 and USN-3627-1 fixed several vulnerabilities in Apache.
This update provides the corresponding update for Ubuntu 12.04 ESM.

Original advisory details:

 Simon Kappel discovered that the Apache HTTP Server mod_auth_digest
 module incorrectly handled threads. A remote attacker with valid
 credentials could possibly use this issue to authenticate using
 another username, bypassing access control restrictions. 
 (CVE-2019-0217)

 Alex Nichols and Jakob Hirsch discovered that the Apache HTTP Server
 mod_authnz_ldap module incorrectly handled missing charset encoding
 headers. A remote attacker could possibly use this issue to cause the
 server to crash, resulting in a denial of service. (CVE-2017-15710)

 Robert Swiecki discovered that the Apache HTTP Server incorrectly
 handled certain requests. A remote attacker could possibly use this
 issue to cause the server to crash, leading to a denial of service.
 (CVE-2018-1301)

 Nicolas Daniels discovered that the Apache HTTP Server incorrectly
 generated the nonce when creating HTTP Digest authentication
 challenges. A remote attacker could possibly use this issue to replay
 HTTP requests across a cluster of servers.
 (CVE-2018-1312)

Update instructions:

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

Ubuntu 12.04 ESM:
  apache2.2-bin                   2.2.22-1ubuntu1.15

In general, a standard system update will make all the necessary
changes.

References:
  https://usn.ubuntu.com/usn/usn-3937-2
  https://usn.ubuntu.com/usn/usn-3937-1
  CVE-2017-15710, CVE-2018-1301, CVE-2018-1312, CVE-2019-0217