CVE-2026-105326 Cups: cups: argument injection in mailto notifier via notify-recipient-uri
Remote attackers can execute arbitrary commands via argument injection in CUPS mailto notifier when email notifications are enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-105326?
CVE-2026-105326 is a low-severity command injection vulnerability in Red Hat Enterprise Linux 10, published on 5 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
An argument injection flaw was found in CUPS. When email notification is configured, the CUPS scheduler accepts printer subscription requests that supply a mailto notify-recipient-uri. The mailto notifier passes the recipient address to the configured sendmail program without ensuring it cannot be interpreted as command-line options. A remote attacker who can reach the CUPS service could supply a crafted recipient value starting with "-" to influence sendmail behavior. Successful exploitation depends on the installed mail transfer agent and CUPS network exposure, and may lead to execution of attacker-controlled commands with the privileges of the CUPS service user.
Weakness: CWE-88
Which versions are affected by CVE-2026-105326?
Linux distribution packages (8)
cups Red Hat:hummingbird:1 | All versions | 0:2.4.19-4.3.hum1 |
cups-client Red Hat:hummingbird:1 | All versions | 0:2.4.19-4.3.hum1 |
cups-devel Red Hat:hummingbird:1 | All versions | 0:2.4.19-4.3.hum1 |
cups-filesystem Red Hat:hummingbird:1 | All versions | 0:2.4.19-4.3.hum1 |
cups-ipptool Red Hat:hummingbird:1 | All versions | 0:2.4.19-4.3.hum1 |
cups-libs Red Hat:hummingbird:1 | All versions | 0:2.4.19-4.3.hum1 |
cups-lpd Red Hat:hummingbird:1 | All versions | 0:2.4.19-4.3.hum1 |
cups-printerapp Red Hat:hummingbird:1 | All versions | 0:2.4.19-4.3.hum1 |
How do I fix CVE-2026-105326?
Apply the vendor's patch.
Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.
Is CVE-2026-105326 being exploited?
There is no known exploitation of CVE-2026-105326 in the wild and no public exploit code.
Sources
Also known as AZL-106743, BELL-CVE-2026-105326, DEBIAN-CVE-2026-105326, ECHO-b398-2098-0d6b, GHSA-r4wf-366f-f6g3, RHSA-2026:77638 and 1 more.