CVE-2023-29919

What it actually does

SolarView Compact firmware versions 6.0 and earlier expose texteditor.php without proper authorization checks. A remote unauthenticated attacker can use that endpoint to read or modify arbitrary files accessible to the web server process. This can disclose configuration files, credentials, logs, application source, and system files, and can also allow tampering with application files or configuration. If an attacker can write PHP or other executable content into a web-served location, the file modification primitive may be escalated to persistent webshell access or device compromise, depending on filesystem permissions and device configuration.

Why it matters to the business

This flaw can allow an external attacker to steal sensitive operational data from SolarView Compact systems and alter files that affect monitoring, reporting, or device behavior. Because exploitation is network-accessible, requires no login, has a high CVSS score, and is reported as weaponized with elevated EPSS likelihood, internet-exposed devices should be treated as high-priority even though the issue is not currently listed in CISA KEV. Compromise may affect the integrity of solar monitoring data, expose credentials reused elsewhere, and create a foothold into connected operational technology or management networks.

How an attack unfolds

An attacker first identifies an exposed SolarView Compact web interface, commonly through internet scanning or by targeting known deployments. They then directly request the vulnerable texteditor.php endpoint without authenticating. By supplying paths to files on the device, the attacker attempts to read sensitive files such as configuration files, credentials, logs, application source, or operating system metadata. The attacker may then use the same endpoint to modify writable files, such as application configuration, web content, scripts, or logs. In higher-impact scenarios, the attacker writes executable content into a web-accessible location and calls it over HTTP to gain persistent command execution, or tampers with monitoring files to hide activity or disrupt trustworthy reporting.

How to fix it

Upgrade SolarView Compact firmware to a vendor-provided version that fixes the unrestricted texteditor.php access issue when available. The provided fixed-version data does not identify a specific patched release, so organizations should consult Contec advisories and support channels for the current secure firmware baseline. Until patched, remove internet exposure, place the interface behind a VPN or management network, restrict access to trusted administrative IP addresses, and block unauthenticated access to /texteditor.php at a reverse proxy, web server, firewall, or WAF. If the endpoint is not operationally required, disable or remove it. After remediation, rotate credentials stored on or accessed by the device, compare application and configuration files against known-good firmware images or backups, and rebuild/reimage devices where unauthorized modification is suspected.

How to confirm the fix worked

Inventory SolarView Compact devices and confirm firmware versions; treat version 6.0 and earlier as affected unless the vendor has provided an explicit backported fix. From an untrusted network path, verify that /texteditor.php is not reachable without authentication and that direct requests are denied with an authentication challenge, 403, or network block. Review perimeter firewall, VPN, reverse-proxy, and WAF policies to confirm the management interface is not internet-exposed. Perform a safe validation using only non-sensitive, non-destructive checks, such as confirming access control behavior rather than modifying files. Validate patching by confirming the installed firmware version, retesting the endpoint authorization requirement, and checking that no arbitrary file path supplied to the endpoint is processed for unauthenticated users.

Typical attack path

1. Scan for exposed SolarView Compact web interfaces.
2. Fingerprint the device or firmware version to identify likely SolarView Compact 6.0 or earlier systems.
3. Send unauthenticated HTTP requests to /texteditor.php.
4. Attempt arbitrary file reads using absolute paths or traversal-style paths to access configuration, credential, log, or system files.
5. Use disclosed information to identify writable locations, credentials, or application structure.
6. Modify files through texteditor.php, such as configuration files, web files, scripts, or logs.
7. Optionally write a web-accessible script or webshell if filesystem permissions allow it.
8. Use the resulting access to persist, pivot, steal additional data, or tamper with monitoring output.

How to detect it

Investigate historical HTTP access logs from the SolarView Compact device, upstream reverse proxies, WAFs, firewalls, VPN concentrators, and network sensors for unauthenticated requests to /texteditor.php. Prioritize requests with path traversal patterns, absolute filesystem paths, sensitive file names, or POST requests that may indicate file modification. Look for follow-on requests to newly created or unusual PHP files, unexpected changes under web directories, modified configuration files, altered timestamps, and log truncation or deletion. Review outbound network telemetry from the device for unusual connections after suspicious texteditor.php activity. Compare device web and configuration directories against a known-good firmware image or backup. If available, correlate source IPs that accessed /texteditor.php with subsequent authentication attempts, configuration changes, or lateral movement. Because threat actors commonly automate exploitation of exposed embedded web interfaces, also hunt for high-volume scanning, repeated 404/200 probes, and requests using encoded traversal sequences.

• /texteditor.php
• GET /texteditor.php
• POST /texteditor.php
• texteditor.php?
• texteditor.php?file=
• texteditor.php?path=
• texteditor.php%3f
• ../
• ..%2f
• %2e%2e%2f
• ..%252f
• /etc/passwd
• /etc/shadow
• /etc/hosts
• /etc/hostname
• /etc/network/interfaces
• /proc/self/environ
• /proc/version
• /var/log/
• /var/www/
• /usr/local/
• /texteditor.php?file=/etc/passwd
• /texteditor.php?path=/etc/passwd

What your security team should do

• Immediately identify SolarView Compact and SolarView Compact firmware deployments, especially internet-facing instances.
• Prioritize remediation for devices running firmware 6.0 or earlier because exploitation is weaponized and the EPSS score indicates meaningful exploitation likelihood.
• Remove public internet exposure and restrict management access to a VPN or tightly scoped administrative network.
• Block unauthenticated HTTP requests to /texteditor.php at network, reverse-proxy, or WAF layers while firmware remediation is pending.
• Upgrade to the latest vendor-supported firmware or apply vendor-recommended mitigations as soon as available.
• Review web, proxy, firewall, and device logs for historical access to /texteditor.php, especially requests containing absolute paths, traversal sequences, or sensitive file names.
• Inspect device files for unauthorized changes, newly created PHP files, modified configuration, altered logs, or unexpected scripts.
• Rotate credentials that may have been stored in configuration files or accessible from the device.
• If compromise is suspected, preserve logs and filesystem evidence before reimaging or restoring from known-good firmware and backups.
• Monitor for follow-on activity from the device to internal systems, unusual outbound connections, or webshell-style requests.