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CVE-2025-14440NVD status: Deferred

JAY Login & Register: Reliance on Cookies without Validation and Integrity Checking

CVE-2025-14440 is a critical-severity reliance on cookies without validation and integrity checking vulnerability in JAY Login & Register from Jayarsiech, 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 JAY Login & Register versions: 2.4.01 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.8% chance of exploitation within 30 days, higher than 57% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of JAY Login & Register you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
JayarsiechJAY Login & Register2.4.01 and earlierNot 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 JAY Login & Register plugin for WordPress is vulnerable to authentication bypass in versions up to, and including, 2.4.01. This is due to incorrect authentication checking in the 'jay_login_register_process_switch_back' function with the 'jay_login_register_process_switch_back' cookie value. This makes it possible for unauthenticated attackers to log in as any existing user on the site, such as an administrator, if they have access to the user id.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Reliance on Cookies without Validation and Integrity Checking

The product relies on the existence or values of cookies when performing security-critical operations, but it does not properly ensure that the setting is valid for the associated user.

How developers prevent this class of flaw

  • Avoid using cookie data for a security-related decision.
  • Perform thorough input validation (i.e.: server side validation) on the cookie data if you're going to use it for a security related decision.
  • Add integrity checks to detect tampering.

More Reliance on Cookies without Validation and Integrity Checking vulnerabilities (CWE-565)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in JAY Login & Register

All JAY Login & Register vulnerabilities

Recent Reliance on Cookies without Validation and Integrity Checking vulnerabilities

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