Vulnerability · Published Apr 3, 2026 · Assigned by GitHub_M
CVE-2026-25726Cloudreve is vulnerable to Account Takeover via Weak Cryptographic Token Generation (Insecure PRNG Seeding)
High 8.1
In plain English
A high-severity security flaw in cloudreve from cloudreve. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/cloudreve/Cloudreve | no fix listed | GO-2026-5350 |
| Go | github.com/cloudreve/Cloudreve/v3 | no fix listed | GO-2026-5350 |
| Go | github.com/cloudreve/Cloudreve/v4 | 4.0.0-20260205113604-ec9fdd33bc54 | GHSA-f8xp-wvcx-p6f4 |
| Go | github.com/cloudreve/Cloudreve/v4 | 4.0.0-20260205113604-ec9fdd33bc54 | GO-2026-5350 |
Affected products (as reported)
Weakness: CWE-338 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/cloudreve/cloudreve/security/advisories/GHSA-f8xp-wvcx-p6f4 x_refsource_CONFIRM
- https://github.com/cloudreve/cloudreve/releases/tag/4.13.0 x_refsource_MISC