How should we interpret CVSS severity scores?

CVSS estimates technical severity, but it does not automatically equal business risk. Prioritize using context like internet exposure, asset criticality, known exploitation, and whether compensating controls exist. A Medium CVSS on an exposed production system can be more urgent than a Critical on an isolated non-production host.

Vulnerability Database

Q: What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

Q: What's the difference between a vulnerability, an exploit, and a zero-day?

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. Risk increases sharply when exploitation becomes reliable or widespread.

Q: Why do vulnerabilities keep reappearing in our environment?

Recurring findings usually come from incomplete asset discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host.

Q: How do we prioritize remediation without burning out the team?

Use a repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress so remediation is steady, not reactive.

Q: How can SynScan help reduce vulnerability risk over time?

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.

365,542

Total vulnerabilities in the database

CVE-2026-45016 — egroupware / egroupware

External Control of File Name or Path

Summary

The function processes image URLs embedded in an HTML email body without validating or restricting URI schemes. The check !str_starts_with($myUrl, 'http') evaluates to true for file:// URIs, causing file_get_contents($basedir . urldecode($myUrl)) to read arbitrary files from the server filesystem and embed them as inline MIME attachments in outgoing email.

str_starts_with('file:///etc/passwd', 'http') → false !false → true

// api/src/Mail.php  
foreach($images[2] as $i =&gt; $url)
			{
				//$isData = false;
				$basedir = $data = &#039;&#039;;
				$needTempFile = true;
				$attachmentData = [&#039;name&#039; =&gt; &#039;&#039;, &#039;type&#039; =&gt; &#039;&#039;, &#039;file&#039; =&gt; &#039;&#039;, &#039;tmp_name&#039; =&gt; &#039;&#039;];
				try
				{
					// do not change urls for absolute images (thanks to corvuscorax)
					if (!str_starts_with($url, &#039;data:&#039;))
					{
						$attachmentData[&#039;name&#039;] = basename($url); // need to resolve all sort of url
						if (($directory = dirname($url)) == &#039;.&#039;) $directory = &#039;&#039;;
						$ext = pathinfo($attachmentData[&#039;name&#039;], PATHINFO_EXTENSION);
						$attachmentData[&#039;type&#039;] = MimeMagic::ext2mime($ext);
						if ( strlen($directory) &gt; 1 &amp;&amp; !str_ends_with($directory, &#039;/&#039;)) { $directory .= &#039;/&#039;; }
..
...
....
// processURL2InlineImages function
if ( $myUrl[0]!=&#039;/&#039; &amp;&amp; strlen($basedir) &gt; 1 &amp;&amp; !str_ends_with($basedir, &#039;/&#039;)) { $basedir .= &#039;/&#039;; }
						if ($needTempFile &amp;&amp; empty($attachment) &amp;&amp; !str_starts_with($myUrl, &quot;http&quot;))
						{
							try {
								$data = file_get_contents($basedir.urldecode($myUrl));
							}
							catch (\Throwable $e) {
								_egw_log_exception($e);
							}
						}
					}
					if (str_starts_with($url, &#039;data:&#039;))

PoC

Log in as any authenticated EGroupware user with mail access and open the mail compose window.
Switch to HTML body mode and insert: <img src="file:///etc/passwd">.
The server executes file_get_contents('file:///etc/passwd'), writes the content to a temp file, and attaches it as an inline MIME part.

Impact

An authenticated attacker can read arbitrary files accessible by the web server process, including /etc/passwd, application configuration files containing database credentials, private TLS keys, and environment files.

Remediation

Enforce a strict URI scheme allowlist before calling file_get_contents(). Replace the check !str_starts_with($myUrl, 'http') with if (!preg_match('#^https?://#i', $myUrl)) { continue; } to reject file://, ftp://, php://, data://, and any other non-HTTP scheme.

Published: Jul 7, 2026
Updated: Jul 8, 2026
CVE: CVE-2026-45016
GHSA: GHSA-c8m7-r2jv-rw63
Severity: Medium
Exploit:
CISA KEV:

CVSS v3:

Severity: Medium
Score: 6.5
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CWEs:

CWE-73

Affected Software
References

Software	From	Fixed in
egroupware / egroupware	26.0.20251208	26.5.20260507
egroupware / egroupware	-	23.1.20260601

https://github.com/EGroupware/egroupware/security/advisories/GHSA-c8m7-r2jv-rw63

Deep Security Visibility Without the Complexity

SynScan provides clear, real-time security insights so you can monitor your attack surface, spot risks early, and act fast—without extra complexity.

No setup fees
5-min deployment
Cancel anytime

Book a Demo

Frequently Asked Questions

What is a Vulnerability (CVE) and why does it matter?

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.