A DjVuLibre security update has been released for Ubuntu Linux 18.04 LTS, 20.04 LTS, 20.10, and 21.04.

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Ubuntu Security Notice USN-4957-1
May 17, 2021

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

- Ubuntu 21.04
- Ubuntu 20.10
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS

Summary:

Several security issues were fixed in DjVuLibre.

Software Description:
- djvulibre: DjVu image format library and tools

Details:

It was discovered that DjVuLibre incorrectly handled certain memory
operations. If a user or automated system were tricked into processing a
specially crafted DjVu file, a remote attacker could cause applications
to hang or crash, resulting in a denial of service, or possibly execute
arbitrary code.

Update instructions:

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

Ubuntu 21.04:
libdjvulibre21 3.5.28-1ubuntu0.1

Ubuntu 20.10:
libdjvulibre21 3.5.27.1-15ubuntu0.1

Ubuntu 20.04 LTS:
libdjvulibre21 3.5.27.1-14ubuntu0.1

Ubuntu 18.04 LTS:
libdjvulibre21 3.5.27.1-8ubuntu0.3

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

References:
  https://ubuntu.com/security/notices/USN-4957-1
CVE-2021-32490, CVE-2021-32491, CVE-2021-32492, CVE-2021-32493,
CVE-2021-3500

Package Information:
  https://launchpad.net/ubuntu/+source/djvulibre/3.5.28-1ubuntu0.1
  https://launchpad.net/ubuntu/+source/djvulibre/3.5.27.1-15ubuntu0.1
  https://launchpad.net/ubuntu/+source/djvulibre/3.5.27.1-14ubuntu0.1
  https://launchpad.net/ubuntu/+source/djvulibre/3.5.27.1-8ubuntu0.3