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Alerts This Week
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Ubuntu 16.04 CUPS Critical Control Character Injection CVE-2026-34980

ubuntu
Calendar Grey July 21, 2026
Scroller Ubuntu
CUPS in Ubuntu could be exploited for remote code execution via crafted print job requests, update recommended immediately.
CUPS could be made to run programs as the lp user if it received specially crafted print job requests.

Summary

CUPS could be made to run programs as the lp user if it received specially crafted print job requests.

Software Description:

- cups: Common UNIX Printing System(tm)

Details:

It was discovered that CUPS did not properly filter control characters in IPP string attributes and PPD keywords. An unauthenticated attacker could exploit this to execute arbitrary code as the lp user on systems with shared target queues.

Topics%20covered

Topics Covered

security advisory critical remote code execution Ubuntu cups control character

Update Instructions

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

Ubuntu 16.04 LTS
  cups                            2.1.3-4ubuntu0.11+esm13
                                  Available with Ubuntu Pro
  cups-bsd                        2.1.3-4ubuntu0.11+esm13
                                  Available with Ubuntu Pro
  cups-client                     2.1.3-4ubuntu0.11+esm13
                                  Available with Ubuntu Pro
  cups-common                     2.1.3-4ubuntu0.11+esm13
                                  Available with Ubuntu Pro
  cups-core-drivers               2.1.3-4ubuntu0.11+esm13
                                  Available with Ubuntu Pro
  cups-daemon                     2.1.3-4ubuntu0.11+esm13
                                  Available with Ubuntu Pro
  libcups2                        2.1.3-4ubuntu0.11+esm13
                                  Available with Ubuntu Pro

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

References

https://ubuntu.com/security/notices/USN-8578-1

CVE-2026-34980

Severity
critical
Lowest
Low
Medium
High
Critical

Ubuntu Security Notice USN-8578-1

Topics%20covered

Topics Covered

security advisory critical remote code execution Ubuntu cups control character

Package Information

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