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GHSA-f8xp-wvcx-p6f4

HIGH

GHSA-f8xp-wvcx-p6f4 is a high-severity (CVSS 8.1) CWE-338 vulnerability in github.com/cloudreve/Cloudreve/v4. O3 Security confirms whether GHSA-f8xp-wvcx-p6f4 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Cloudreve is vulnerable to Account Takeover via Weak Cryptographic Token Generation (Insecure PRNG Seeding)

Also known asCVE-2026-25726GO-2026-5350
Published
Mar 31, 2026
Updated
Jun 25, 2026
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed

Real-World Exposure

1 pkg affected
🐹github.com/cloudreve/Cloudreve/v4

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Impact

This vulnerability affects Cloudreve instances that were first deployed/initialized with versions prior to V4.10.0.

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.

Note: Servers running V4.10.0+ are still vulnerable if they were originally installed using an older version, as the weak secrets persist in the configuration.

Patches

The issue has been addressed in version 4.13.0. This patch introduces a migration mechanism that automatically:

  1. Invalidate the existing secret_key.
  2. Regenerate a new, cryptographically secure secret_key using crypto/rand.

Users should upgrade to 4.13.0 immediately.

Workarounds

If an immediate upgrade is not possible, administrators must manually rotate the critical secrets in the configuration file to invalidate potential exploits:

  1. Stop the Cloudreve service.
  2. In Cloudreve database, locate secret_key setting.
  3. Replace the value with a long, random string (e.g., generated via openssl rand -base64 64).
  4. Restart the Cloudreve service.

Note: This will log out all currently active users.

Resources

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
🐹Gogithub.com/cloudreve/Cloudreve/v4all versions4.0.0-20260205113604-ec9fdd33bc54

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/cloudreve/Cloudreve/v4. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update github.com/cloudreve/Cloudreve/v4 to 4.0.0-20260205113604-ec9fdd33bc54 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-f8xp-wvcx-p6f4 is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether GHSA-f8xp-wvcx-p6f4 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-f8xp-wvcx-p6f4. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Impact This vulnerability affects **Cloudreve** instances that were **first deployed/initialized** with versions prior to V4.10.0. 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 validat
O3 Security · Impact-Aware SCA

Is GHSA-f8xp-wvcx-p6f4 in your dependencies?

O3 detects GHSA-f8xp-wvcx-p6f4 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.