---
id: CVE-2026-102577
title: A flaw was found in Moodle
summary: >-
  A flaw was found in Moodle. Incorrect handling of IPv4-mapped IPv6 addresses
  within the URL downloader's host-blocking logic allows an authenticated remote
  user to bypass blocked-host restrictions. By supplying a crafted URL, an
  attacker…
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'
cwe:
  - CWE-918
product: moodle
affected:
  - moodle >= 5.2.0 < 5.2.2
  - moodle >= 5.1.0 < 5.1.6
  - moodle >= 5.0.0 < 5.0.9
  - moodle < 4.5.13
published: '2026-09-30'
updated: '2026-09-30'
sourceUpdated: '2026-09-30T09:17:14.660'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-102577'
references:
  - url: >-
      http://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-88779
    label: patrick@puiterwijk.org
  - url: 'https://access.redhat.com/security/cve/CVE-2026-102577'
    label: patrick@puiterwijk.org
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2543604'
    label: patrick@puiterwijk.org
  - url: 'https://moodle.org/mod/forum/discuss.php?d=482495'
    label: patrick@puiterwijk.org
tags:
  - nvd
  - cve.org
ingestedAt: '2026-09-30T09:00:29.910Z'
---

## Overview

A flaw was found in Moodle. Incorrect handling of IPv4-mapped IPv6 addresses within the URL downloader's host-blocking logic allows an authenticated remote user to bypass blocked-host restrictions. By supplying a crafted URL, an attacker can induce the server to make requests to restricted destinations, leading to Server-Side Request Forgery (SSRF).

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.