CVE-2025-12758CWE-792

Versions of the package validator before 13.15.22 are vulnerable to Incomplete Filtering of One or More Instances of Special Elements in the isLength()…

High · published November 27, 2025

CVSS v4.0
8.7
EPSS
1%
Percentile
42.1
In the wild
Unconfirmed
What it is

⚡ A sneaky oversight in string length validation could let attackers slip massive inputs right past the gates! Think of it like a restaurant that forgets to check the portion sizes on the plates — if they don't get it right, diners might walk away stuffed or, worse, cause a food fight when their orders overflow! This vulnerability could allow an attacker to submit input strings much longer than your application is ready to handle. The fallout? You could end up with data truncation in your databases, buffer overflows in system components, or even a denial-of-service situation that brings your app to its knees!

Put simply

Think of it like a restaurant that forgets to check the portion sizes on the plates — if they don't get it right, diners might walk away stuffed or, worse, cause a food fight when their orders overflow! The isLength() function in versions prior to 13.15.22 fails to filter Unicode variation selectors, allowing inputs to exceed expected lengths, leading to various vulnerabilities including buffer overflows and data corruption.

What to do

This vulnerability could allow an attacker to submit input strings much longer than your application is ready to handle. The fallout? You could end up with data truncation in your databases, buffer overflows in system components, or even a denial-of-service situation that brings your app to its knees! To safeguard against this, update the validator package to version 13.15.22 or later immediately. Additionally, review your input validation mechanisms to ensure they can handle unexpected characters appropriately. You've got this! By taking these steps, you're on the way to becoming a security hero! 🛡️

The record
Technical detail
CVSS v4.0
8.7 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P
EPSS
0.00517 · 42.1th percentile
Weakness
CWE-792 · Incomplete Filtering of One or More Instances of Special Elements
Published
2025-11-27T05:00Z
EPSS history
Timeline
  • 27 NOV 05:00Z
    Versions of the package validator before 13.15.22 are vulnerable to Incomplete Filtering of One or More Instances of Special Elements in the isLength()…
    cvelistv5