CVE-2026-63089: Weak RNG (CVSS 9.3)

Description

WireGuard Easy through 15.3.0, fixed in commit 66b292b, contains a cryptographically weak one-time link token generation vulnerability that allows unauthenticated network attackers to recover WireGuard peer credentials by brute-forcing a keyspace of at most 1000 candidate tokens per client ID, as the token is computed using CRC32 over a random value constrained to 0-999. Attackers can enumerate candidate tokens against the unauthenticated /cnf/:oneTimeLink route, which lacks rate limiting and does not validate token expiration, to obtain a peer's PrivateKey and PresharedKey and impersonate that peer on the VPN network.

Is your site exposed to CVE-2026-63089?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

9.3

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N

EPSS — Exploit Prediction

0.0024

Probability of exploitation

0.15%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-338 CWE-338

CWE-613 CWE-613

References

Other References

https://github.com/wg-easy/wg-easy/commit/66b292b11bde3664f05ffb016c8082665d261ded https://github.com/wg-easy/wg-easy/pull/2661 https://www.vulncheck.com/advisories/wireguard-easy-weak-token-generation-information-disclosure-via-otl-route

Frequently Asked Questions

What is CVE-2026-63089? +

WireGuard Easy through 15.3.0, fixed in commit 66b292b, contains a cryptographically weak one-time link token generation vulnerability that allows unauthenticated network attackers to recover WireGuard peer credentials by brute-forcing a keyspace of at most 1000 candidate tokens per client ID, as the token is computed using CRC32 over a random value constrained to 0-999. Attackers can enumerate candidate tokens against the unauthenticated /cnf/:oneTimeLink route, which lacks rate limiting and does not validate token expiration, to obtain a peer's PrivateKey and PresharedKey and impersonate that peer on the VPN network. It has a CVSS v3.1 base score of 9.3 (CRITICAL).

How severe is CVE-2026-63089? +

CVE-2026-63089 has a CVSS v3.1 score of 9.3 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0024, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-63089? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-8169

ExtremeXOS (EXOS) uses a challenge-response mechanism to authorize access to the privileged debug-mode function. The challenge value is generated using …

CVE-2025-21617

Guzzle OAuth Subscriber signs Guzzle requests using OAuth 1.0. Prior to 0.8.1, Nonce generation does not use sufficient entropy nor …

CVE-2026-42155

Magento Long Term Support (LTS) is an unofficial, community-driven project provides an alternative to the Magento Community Edition e-commerce platform …

CVE-2025-54883

Vision UI is a collection of enterprise-grade, dependency-free modules for modern web projects. In versions 1.4.0 and below, the getSecureRandomInt …

CVE-2025-26379

Use of a weak pseudo-random number generator, which may allow an attacker to read or inject encrypted PowerG packets.

CVE-2026-11347

The linqi application contains hardcoded cryptographic keys. Additionally, the application uses a weak algorithm with a limited ASCII charset to …

CVE-2026-63089