OTP Login With Phone Number, OTP Verification: Improper Authentication
CVE-2026-3655 is a critical-severity improper authentication vulnerability in OTP Login With Phone Number, OTP Verification from Glboy, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected OTP Login With Phone Number, OTP Verification versions: 1.8.50 through 1.8.60. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.51% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of OTP Login With Phone Number, OTP Verification you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Glboy | OTP Login With Phone Number, OTP Verification | 1.8.50 through 1.8.60 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (wordfence.com).
Official description
The OTP Login With Phone Number, OTP Verification plugin for WordPress is vulnerable to authentication bypass in versions 1.8.50 through 1.8.60. This is due to the Firebase verification flow in the `lwp_ajax_register` AJAX handler not binding the Firebase session to the phone number supplied in the request. The `idehweb_lwp_activate_through_firebase()` function validates that a Firebase OTP session is legitimate, but the `phoneNumber` returned by Firebase is never compared against the victim's stored phone number. This makes it possible for unauthenticated attackers to authenticate as any user who has a phone number stored in user meta, including administrators, by verifying their own Firebase session and supplying the victim's phone number in the same request.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Authentication
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
How developers prevent this class of flaw
- Use an authentication framework or library such as the OWASP ESAPI Authentication feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
- plugins.trac.wordpress.org/browser/login-with-phone-number/tags/1.8.60/inc/ajax-handlers.php#L1167
- plugins.trac.wordpress.org/browser/login-with-phone-number/tags/1.8.60/inc/ajax-handlers.php#L649
- plugins.trac.wordpress.org/browser/login-with-phone-number/tags/1.8.60/inc/ajax-handlers.php#L659
- plugins.trac.wordpress.org/browser/login-with-phone-number/trunk/inc/ajax-handlers.php#L649
- plugins.trac.wordpress.org/changeset/3479314/login-with-phone-number/trunk/inc/ajax-handlers.php?old=3455810&…
- wordfence.com/threat-intel/vulnerabilities/id/7fc410f2-5f2b-4eea-a0fb-fe58f988f95f?source=cve
Other vulnerabilities in OTP Login With Phone Number, OTP Verification
- 8.1 High severity
- 8.8 High severity
- 8.1 High severity
- 9.8 Critical severity
- 8.8 High severity
Recent Improper Authentication vulnerabilities
- 7.5 High severity
- 9.8 Critical severity
- 7.4 High severity
- 9.3 Critical severity
- 7.1 High severity
- 9.1 Critical severity
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