---
id: CVE-2026-25726
title: Cloudreve is a self-hosted file management and sharing system
summary: >-
  Cloudreve is a self-hosted file management and sharing system. Prior to
  version 4.13.0, the application uses the weak pseudo-random number generator
  math/rand seeded with time.Now().UnixNano() to generate critical security
  secrets, inclu…
severity: high
cvss: 8.1
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-338
vendor: cloudreve
product: cloudreve
affected:
  - cloudreve < 4.13.0
patched:
  - cloudreve 4.13.0
published: '2026-04-03'
updated: '2026-07-24'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-25726'
references:
  - url: 'https://github.com/cloudreve/cloudreve/releases/tag/4.13.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/cloudreve/cloudreve/security/advisories/GHSA-f8xp-wvcx-p6f4
    label: security-advisories@github.com
tags:
  - nvd
epss: 0.00501
epssPercentile: 0.4045
ingestedAt: '2026-07-25T22:05:04.502Z'
---

## Overview

Cloudreve is a self-hosted file management and sharing system. Prior to version 4.13.0, the application uses the weak pseudo-random number generator math/rand seeded with time.Now().UnixNano() to generate critical security secrets, including the secret_key, and hash_id_salt. These secrets are generated upon first startup and persisted in the database. An attacker can exploit this by obtaining the administrator's account creation time (via public API endpoints) to narrow the search window for the PRNG seed, and use known hashid to validate the seed. By brute-forcing the seed (demonstrated to take <3 hours on general consumer PC), an attacker can predict the secret_key. This allows them to forge valid JSON Web Tokens (JWTs) for any user, including administrators, leading to full account takeover and privilege escalation. This issue has been patched in version 4.13.0.

## Affected

- `cloudreve < 4.13.0`

## Remediation

Upgrade past the affected range:

- `cloudreve 4.13.0`