---
title: "CVE-2026-55579: Pheditor: Hardcoded default password 'admin' with no forced change enables full application compromise"
url: https://erroneo.us/security/cve/CVE-2026-55579/
description: "CVE-2026-55579 (pheditor/pheditor (Composer (PHP))): Pheditor is a single-file editor and file manager written in PHP. From version 2.0.1 to before version…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-07-27
date_modified: 2026-07-27
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-55579"
kev: false
cvss: 9.8
epss: 0.00792
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-55579: Pheditor: Hardcoded default password 'admin' with no forced change enables full application compromise

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.8% , percentile 56: FIRST’s model estimates a 0.8% chance of exploitation activity in the next 30 days, higher than 56% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes pheditor/pheditor (Composer (PHP)) >= 2.0.1, < 2.0.6, fixed in 2.0.6 . Check your lockfile, including transitive dependencies.

## What it is

Pheditor is a single-file editor and file manager written in PHP. From version 2.0.1 to before version 2.0.6, 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. This issue has been patched in version 2.0.6.

## Affected packages

- Composer (PHP) `pheditor/pheditor` >= 2.0.1, < 2.0.6 → fixed: 2.0.6

## Affected products (CVE record)

- pheditor pheditor: >= 2.0.1, < 2.0.6

## Severity

- GitHub_M CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`
- GitHub CVSS 3.1: 9.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact total .
- FIRST EPSS (model of 2026-10-21): 0.79% probability of exploitation activity in the next 30 days; percentile 56.

## Sources

- [GitHub Advisory GHSA-p4h7-p9rj-2pq2](https://github.com/advisories/GHSA-p4h7-p9rj-2pq2)
- [CVE.org record CVE-2026-55579](https://www.cve.org/CVERecord?id=CVE-2026-55579)
- [NVD entry CVE-2026-55579](https://nvd.nist.gov/vuln/detail/CVE-2026-55579)
- [github.com](https://github.com/pheditor/pheditor/security/advisories/GHSA-p4h7-p9rj-2pq2)
- [github.com](https://github.com/pheditor/pheditor/releases/tag/2.0.6)

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Source page: https://erroneo.us/security/cve/CVE-2026-55579/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt