CVE-2026-48098: NexTor IP Changer Privilege Escalation

CVE-2026-48098 Overview

CVE-2026-48098 affects NexTor IP Changer, a command-line tool that rotates a user's IP address through the Tor network. Versions prior to 2.0.0 execute privileged system commands using sudo combined with shell=True directly inside application logic. When the host has passwordless sudo (NOPASSWD) enabled, the tool executes privileged commands silently without explicit user confirmation. This weakness is classified under [CWE-78] as improper neutralization of special elements used in an OS command. Version 2.0.0 remediates the issue.

Critical Impact
A local attacker with access to the user account running NexTor IP Changer can trigger privileged command execution on systems configured with NOPASSWD sudo, leading to high impact on confidentiality and integrity.

Affected Products

NexTor IP Changer versions prior to 2.0.0
Linux hosts configured with passwordless sudo (NOPASSWD)
Environments where the tool is invoked by users with sudoers entries

Discovery Timeline

2026-08-07 - CVE-2026-48098 published to NVD
2026-08-07 - Last updated in NVD database

Technical Details for CVE-2026-48098

Vulnerability Analysis

NexTor IP Changer invokes system utilities to restart the Tor service and reconfigure network state. The application constructs command strings and passes them to a subprocess call with shell=True, prefixing operations with sudo. Passing shell=True instructs the interpreter to evaluate the command through a shell, which parses metacharacters such as ;, &&, |, and backticks.

Because the privileged commands run through sudo without an interactive password prompt on systems with NOPASSWD, execution proceeds silently. An attacker who influences any component of these command strings can inject additional shell operations that execute with root privileges. The tool provides no explicit user confirmation step before invoking the elevated action.

Root Cause

The root cause is unsafe process invocation. Combining sudo, shell=True, and dynamically constructed command strings violates the principle of least privilege and enables OS command injection [CWE-78]. Passwordless sudo removes the human-in-the-loop check that would otherwise prevent silent privilege escalation.

Attack Vector

Exploitation requires local access with low privileges and no user interaction. An attacker leverages the tool's execution context to run arbitrary commands as root through the sudoers policy. The scope remains unchanged, but confidentiality and integrity impacts are high because the attacker gains root-level command execution on the host.

No verified public proof-of-concept code is available. See the GitHub Security Advisory for maintainer-provided technical detail.

Detection Methods for CVE-2026-48098

Indicators of Compromise

Unexpected sudo invocations spawned by the NexTor IP Changer Python process without a corresponding TTY password prompt
Child processes of the tool executing shell metacharacters or commands unrelated to Tor service management
Modifications to /etc/sudoers or /etc/sudoers.d/ granting NOPASSWD to accounts running the tool

Detection Strategies

Audit sudoers configurations for NOPASSWD entries associated with users who run the tool.
Alert on process telemetry where python or the NexTor binary is the parent of sudo followed by non-Tor commands.
Review command-line arguments in EDR telemetry for shell metacharacters passed to privileged operations.

Monitoring Recommendations

Enable Linux auditd rules on execve calls involving sudo to capture full command lines.
Forward process creation events to a central data lake for correlation across hosts.
Baseline the tool's expected command patterns and alert on deviations.

How to Mitigate CVE-2026-48098

Immediate Actions Required

Upgrade NexTor IP Changer to version 2.0.0 or later on all systems where it is installed.
Remove NOPASSWD sudo entries for accounts that execute the tool until upgrade is complete.
Restrict execution of the tool to trusted administrators on isolated systems.

Patch Information

The maintainer released version 2.0.0, which removes the unsafe sudo plus shell=True invocation pattern from application logic. Users should install the fixed release from the project repository referenced in the GitHub Security Advisory GHSA-fpxg-q9p5-5wvm.

Workarounds

Require an interactive password for sudo by removing NOPASSWD from the relevant sudoers rules.
Run the tool only inside a dedicated, non-privileged virtual machine or container.
Restrict sudoers entries to explicit binaries rather than broad command wildcards.

bash

# Configuration example: restrict sudoers to specific Tor management commands only
# Edit with: sudo visudo -f /etc/sudoers.d/nextor
user ALL=(root) /bin/systemctl restart tor, /bin/systemctl status tor
# Do NOT use: user ALL=(root) NOPASSWD: ALL