CVE-2022-40022

What it actually does

This is a remotely reachable command injection vulnerability in Microchip/Microsemi SyncServer S650 firmware. An unauthenticated attacker can send crafted input to a vulnerable management interface or service that is passed to an operating-system shell without proper sanitization, causing attacker-supplied commands to execute on the appliance. Because the CVSS vector indicates network access, low complexity, no privileges, and no user interaction, successful exploitation can provide full confidentiality, integrity, and availability impact on the device, including command execution, configuration manipulation, persistence, data access, or service disruption.

Why it matters to the business

SyncServer S650 devices provide trusted time synchronization, so compromise can affect more than the appliance itself: attackers may disrupt accurate timekeeping, tamper with configuration, pivot from a trusted infrastructure device, or impair logging, authentication, certificate validation, and incident response timelines that depend on reliable time. The vulnerability is weaponized and has a very high EPSS score, meaning exploitation is likely in the wild even though it is not currently listed in CISA KEV; internet-exposed or broadly reachable management interfaces should be treated as urgent risk.

How an attack unfolds

An attacker first identifies a reachable SyncServer S650 management surface, commonly by scanning for exposed appliance web or administrative services. They then send a specially crafted request containing shell metacharacters or command separators in a vulnerable parameter. The appliance processes the input unsafely and invokes a system shell, causing the injected command to run with the privileges of the affected service. The attacker may use initial commands for proof of execution, such as retrieving system identity or writing a file, then download tooling, add users or keys, alter device configuration, disrupt NTP/time services, or use the appliance as a foothold for internal reconnaissance. Because exploitation requires no authentication or user interaction, exposed devices can be attacked opportunistically and at scale.

How to fix it

Upgrade SyncServer S650 firmware to a vendor-supported release that fixes the command injection issue. No fixed version was provided in the supplied data, so administrators should consult the latest Microchip/Microsemi SyncServer S650 security advisories and firmware release notes, then apply the newest available security update. Until patched, restrict management access to trusted administrative networks only, block internet exposure, enforce VPN or bastion access, apply firewall allowlists, disable unused administrative services, rotate credentials and keys that may have been stored on or accessible from the appliance, and monitor the device for signs of command execution or configuration tampering. If compromise is suspected, rebuild or reimage from trusted firmware, restore known-good configuration, and rotate any secrets or trust relationships associated with the device.

How to confirm the fix worked

Confirm the exact appliance model and firmware version from the device administrative interface or vendor-supported CLI and verify it is at or above the vendor-fixed firmware level. Validate that management interfaces are not reachable from untrusted networks using external and internal scanning. Review firewall rules, ACLs, VPN policies, and exposure-management data to ensure access is limited to authorized administrative sources. Where permitted, use a safe authenticated vulnerability scanner or vendor-provided validation method to check for the vulnerable firmware; avoid sending live command-injection payloads to production time infrastructure unless explicitly approved. Confirm NTP/time services remain operational and that device configuration, administrative accounts, SSH keys, scheduled tasks, and startup scripts match a known-good baseline.

Typical attack path

1. Scan for reachable Microchip/Microsemi SyncServer S650 appliances or exposed management interfaces.
2. Fingerprint the service or firmware version to identify likely vulnerable targets.
3. Send crafted input containing shell command separators or substitutions to the vulnerable interface.
4. Execute a simple command to confirm code execution, such as reading system information or creating a temporary file.
5. Run follow-on commands to download tools, establish persistence, change configuration, or disrupt time synchronization services.
6. Use the compromised appliance to pivot, collect sensitive configuration, impair logging accuracy, or support further intrusion activity.

How to detect it

Investigate whether exploitation already occurred by reviewing management web access logs, reverse proxy logs, firewall logs, IDS/IPS alerts, authentication and administrative audit logs, system logs, process execution history if available, configuration change history, firmware update history, and outbound network telemetry from the appliance. Look for unauthenticated or unexpected requests containing shell metacharacters, command separators, command substitution syntax, URL-encoded payloads, or attempts to invoke common Linux utilities. Pay particular attention to requests followed by outbound connections from the appliance to unfamiliar IP addresses, downloads into temporary directories, changes to administrative users, SSH authorized keys, cron jobs or startup scripts, altered NTP configuration, service restarts, unexplained firmware/configuration exports, or time-service disruption. Since command injection may leave limited local telemetry on embedded appliances, correlate network data with configuration baselines and preserve device logs before rebooting or reimaging.

• ;id
• ; uname -a
• |id
• | uname -a
• `id`
• $(id)
• %3Bid
• %7Cid
• %60id%60
• %24%28id%29
• /bin/sh -c
• /bin/bash -c
• wget http
• curl http
• tftp -g
• ftpget
• busybox wget
• chmod +x /tmp
• /tmp/
• /var/tmp/
• /dev/shm/
• nc -e
• netcat -e
• bash -i
• /bin/busybox
• authorized_keys
• crontab -e
• /etc/cron
• /etc/init.d
• /etc/rc.local

What your security team should do

• Treat internet-exposed or broadly reachable SyncServer S650 appliances as urgent patching priorities because exploitation is weaponized and EPSS likelihood is very high.
• Inventory all SyncServer S650 appliances and confirm firmware versions, network exposure, and administrative access paths.
• Apply the latest vendor firmware update that remediates the command injection vulnerability; if no update is immediately available, isolate management interfaces behind VPN, bastions, and strict source allowlists.
• Search historical logs for suspicious command-injection patterns, unexpected outbound connections, file downloads, shell execution, and changes to appliance configuration.
• If indicators of compromise are found, remove the device from service, preserve logs and forensic artifacts, reimage or factory-reset with trusted firmware, restore known-good configuration, and rotate credentials, SSH keys, API keys, and shared secrets.
• Monitor time synchronization integrity and compare appliance time outputs against independent trusted time sources after remediation.
• Add detections for command-injection attempts against appliance management interfaces and for unusual outbound traffic from time infrastructure devices.