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Ubuntu Security Notice USN-6584-2
February 21, 2024
libspf2 vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 16.04 LTS (Available with Ubuntu Pro)
Summary:
Several security issues were fixed in Libspf2.
Software Description:
- libspf2: Sender Policy Framework for SMTP authorization
Details:
USN-6584-1 fixed several vulnerabilities in Ubuntu 18.04 LTS and
Ubuntu 20.04 LTS. This update provides the corresponding updates for
CVE-2021-33912 and CVE-2021-33913 in Ubuntu 16.04 LTS.
We apologize for the inconvenience.
Original advisory details:
  Philipp Jeitner and Haya Shulman discovered that Libspf2 incorrectly handled
  certain inputs. If a user or an automated system were tricked into opening a
  specially crafted input file, a remote attacker could possibly use this issue
  to cause a denial of service or execute arbitrary code. (CVE-2021-20314)
  It was discovered that Libspf2 incorrectly handled certain inputs. If a user or
  an automated system were tricked into opening a specially crafted input file, a
  remote attacker could possibly use this issue to cause a denial of service or
  execute arbitrary code. This issue only affected Ubuntu 18.04 LTS and
  Ubuntu 20.04 LTS. (CVE-2021-33912, CVE-2021-33913)
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 16.04 LTS (Available with Ubuntu Pro):
   libmail-spf-xs-perl             1.2.10-6ubuntu0.1~esm2
   libspf2-2                       1.2.10-6ubuntu0.1~esm2
   libspf2-dev                     1.2.10-6ubuntu0.1~esm2
   spfquery                        1.2.10-6ubuntu0.1~esm2
In general, a standard system update will make all the necessary changes.
References:
   https://ubuntu.com/security/notices/USN-6584-2
   https://ubuntu.com/security/notices/USN-6584-1
   CVE-2021-33912, CVE-2021-33913