USN-8518-1: mailcap vulnerability

Q: Who is exposed to this issue?

Systems using the cautious-launcher utility from Ubuntu's mailcap package are exposed where a sandboxed application can invoke it with affected file types.

Q: What does an attacker need to exploit it?

An attacker needs a way to trigger handling of certain file types through cautious-launcher from within a sandboxed application. Successful exploitation allows the attacker to escape the sandbox and execute arbitrary code on the host operating system.

Published Jul 8, 2026

Updated

Aaron Rainbolt discovered that the cautious-launcher utility in the mailcap package did not properly restrict the execution of certain file types. An attacker could use this issue to escape a sandboxed application and execute arbitrary code on the host operating system.

Affected Software

8 affected componentsFixes available

All of the following

ubuntu/mailcap<3.75ubuntu1.1

3.75ubuntu1.1

Ubuntu Ubuntu=26.04

All of the following

ubuntu/mailcap<3.74ubuntu1.1

3.74ubuntu1.1

Ubuntu Ubuntu=25.10

All of the following

ubuntu/mailcap<3.70+nmu1ubuntu1.24.04.1

3.70+nmu1ubuntu1.24.04.1

Ubuntu Ubuntu=24.04

All of the following

ubuntu/mailcap<3.70+nmu1ubuntu1.22.04.1

3.70+nmu1ubuntu1.22.04.1

Ubuntu Ubuntu=22.04

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Upgrade
Upgrade ubuntu/mailcap to a version that resolves this vulnerability.
Fixed in 3.75ubuntu1.1
Upgrade
Upgrade ubuntu/mailcap to a version that resolves this vulnerability.
Fixed in 3.74ubuntu1.1
Upgrade
Upgrade ubuntu/mailcap to a version that resolves this vulnerability.
Fixed in 3.70+nmu1ubuntu1.24.04.1
Upgrade
Upgrade ubuntu/mailcap to a version that resolves this vulnerability.
Fixed in 3.70+nmu1ubuntu1.22.04.1
Upgrade
Upgrade mailcap to a version that resolves this vulnerability.
Patch USN-8518-1

Event History

Jul 8, 2026

Advisory Published

via Ubuntu·12:00 AM

Data Sourced

via Ubuntu·12:00 AM

DescriptionAffected Software

Child vulnerabilities

Contains the following vulnerabilities.

CVE-2026-10037

Frequently Asked Questions

Who is exposed to this issue?

Systems using the cautious-launcher utility from Ubuntu's mailcap package are exposed where a sandboxed application can invoke it with affected file types.

What does an attacker need to exploit it?

An attacker needs a way to trigger handling of certain file types through cautious-launcher from within a sandboxed application. Successful exploitation allows the attacker to escape the sandbox and execute arbitrary code on the host operating system.

USN-8518-1: mailcap vulnerability

Affected Software

Remediation

Event History

Child vulnerabilities

Frequently Asked Questions

Who is exposed to this issue?

What does an attacker need to exploit it?

Company

Resources

Contact

Frequently Asked Questions

Who is exposed to this issue?

What does an attacker need to exploit it?