CVE-2026-38993

Cockpit's remote login feature passes user-supplied hostnames and usernames from the web interface to the SSH client without validation. An attacker with network access to the Cockpit web service can craft a single HTTP request to the login endpoint that injects malicious SSH options or shell commands, achieving code execution on the Cockpit host without valid credentials.

A vulnerability in Cockpit allows an unauthenticated remote attacker to initiate and sustain numerous simultaneous connections to the cockpit-tls service, forcing it to create an unbounded number of threads and consume system resources such as memory and file descriptors. The result is a denial of service (DoS).

A vulnerability in Cockpit on ILP32 builds involves an integer overflow in the `do_lastlog()` function, specifically in offset calculation for lastlog entries. A low-privileged user with a specially provisioned large UID can cause the offset to wrap, allowing unauthorized reads and writes to other users' lastlog records, potentially disclosing or altering login information.

A flaw was found in Cockpit that allows a remote attacker to execute arbitrary commands on the host by exploiting unsanitized user-controlled parameters in the system logs UI. An attacker can inject shell metacharacters and command substitutions, leading to arbitrary shell command execution on the affected system.