All vulnerabilities
CVE-2026-102577

Moodle: ssrf risk in url downloader via ipv4-mapped ipv6 address bypass

Unknown productApplications & CMS
CVSS
4.3Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.25%Chance of exploitation activity in the next 30 days, higher than 15% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in5.2.2Also 5.1.6, 5.0.9 and 1 moreCVE List
Published30 Sep 2026Updated 30 Sep 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

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).

Text from CVE List

Affected versions 4

  • Productaffected: 5.2.0 before 5.2.2CVE List
  • Productaffected: 5.1.0 before 5.1.6CVE List
  • Productaffected: 5.0.0 before 5.0.9CVE List
  • Productaffected: all versions before 4.5.13CVE List

References 3