---
id: "CVE-2026-126377"
page: "https://infrastack.ai/live/CVE-2026-126377"
kind: "vulnerability"
aliases: ["CVE-2026-126377"]
title: "Vvveb: loose comparison in login cookie lets attackers take over accounts"
severity: "critical"
cvss: 9.2
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["cms", "package", "php", "self-hosted", "vvveb"]
not_affected_if: ["version-1.0.9.0-or-later"]
published_at: "2026-11-13T10:17:40+00:00"
first_seen_at: "2026-11-13T10:47:17+00:00"
updated_at: "2026-11-13T10:48:35+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-126377", "first_seen_at": "2026-11-13T10:47:17+00:00"}]
exploit_sources: []
---

# Vvveb: loose comparison in login cookie lets attackers take over accounts

Link for people: https://infrastack.ai/live/CVE-2026-126377 (this .md is for agents)

Vvveb is a PHP content management system whose login cookie check uses a loose comparison on MD5 hashes. An unauthenticated attacker can brute-force a cookie value that hashes to a magic 0e string and forge a persistent cookie to take over any account.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the Vvveb version in use: versions below `1.0.9.0` are listed as affected.
- Look at `system/user/user.php` for the `generateCookie()` function and whether it compares hashes with `==`.

## Fix

- Vvveb: move to `1.0.9.0` or later.

## Timeline

- 2026-11-13T10:47:17+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-126377

## Documents

- [advisory] Vendor advisory: github.com https://github.com/givanz/Vvveb/security/advisories/GHSA-p8w8-2rq6-wm2g
- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/vvveb-before-1.0.9.0-cookie-forgery-via-php-type-juggling-in-generatecookie

## From the sources

Vvveb before 1.0.9.0 contains an authentication bypass vulnerability in generateCookie() in system/user/user.php that uses loose comparison to validate MD5 cookie hashes. Unauthenticated attackers can brute-force cookie values until the server's MD5 computation yields a 0e magic hash, then forge persistent cookies for account takeover.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_