CVE-2026-18056

HIGH
Published Sep 6, 2026 Modified Sep 8, 2026 CWE-287

Description

The HivePress Authentication plugin for WordPress is vulnerable to Authentication Bypass via the access_token parameter in all versions up to, and including, 1.1.4. This is due to the authenticate_user function's Facebook authenticator resolving third-party identity by forwarding the attacker-supplied access_token to the Facebook Graph API and trusting the returned email and ID verbatim, without performing any application ID or audience validation — specifically, no /debug_token verification and no comparison of the token's app_id against the configured hp_facebook_app_id. This makes it possible for unauthenticated attackers to authenticate as any existing WordPress user, including administrators, whose email address is associated with a Facebook account for which the attacker can obtain any valid access token. Important Note: To exploit the vulnerability, the attacker must obtain the victim's access token.

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CVSS v3.1 Score

7.5
HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0034
Probability of exploitation
0.28%
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-287 Improper Authentication

References

Frequently Asked Questions

What is CVE-2026-18056? +
The HivePress Authentication plugin for WordPress is vulnerable to Authentication Bypass via the access_token parameter in all versions up to, and including, 1.1.4. This is due to the authenticate_user function's Facebook authenticator resolving third-party identity by forwarding the attacker-supplied access_token to the Facebook Graph API and trusting the returned email and ID verbatim, without performing any application ID or audience validation — specifically, no /debug_token verification and no comparison of the token's app_id against the configured hp_facebook_app_id. This makes it possible for unauthenticated attackers to authenticate as any existing WordPress user, including administrators, whose email address is associated with a Facebook account for which the attacker can obtain any valid access token. Important Note: To exploit the vulnerability, the attacker must obtain the victim's access token. It has a CVSS v3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-18056? +
CVE-2026-18056 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0034, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-18056? +
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.

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