A QPDF security update has been released for Ubuntu Linux 18.04 LTS and 20.04 LTS.

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Ubuntu Security Notice USN-5026-1
July 29, 2021

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

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

Several security issues were fixed in QPDF.

Software Description:
- qpdf: tools for transforming and inspecting PDF files

Details:

It was discovered that QPDF incorrectly handled certain malformed PDF
files. A remote attacker could use this issue to cause QPDF to consume
resources, resulting in a denial of service. This issue only affected
Ubuntu 18.04 LTS. (CVE-2018-18020)

It was discovered that QPDF incorrectly handled certain malformed PDF
files. A remote attacker could use this issue to cause QPDF to crash,
resulting in a denial of service, or possibly execute arbitrary code.
(CVE-2021-36978)

Update instructions:

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

Ubuntu 20.04 LTS:
libqpdf26 9.1.1-1ubuntu0.1
qpdf 9.1.1-1ubuntu0.1

Ubuntu 18.04 LTS:
libqpdf21 8.0.2-3ubuntu0.1
qpdf 8.0.2-3ubuntu0.1

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

References:
  https://ubuntu.com/security/notices/USN-5026-1
CVE-2018-18020, CVE-2021-36978

Package Information:
  https://launchpad.net/ubuntu/+source/qpdf/9.1.1-1ubuntu0.1
  https://launchpad.net/ubuntu/+source/qpdf/8.0.2-3ubuntu0.1