Bug 2543604 (CVE-2026-102577)

Summary: CVE-2026-102577 moodle: SSRF risk in URL downloader via IPv4-mapped IPv6 address bypass
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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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).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2543833    
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Description OSIDB Bzimport 2026-09-29 20:24:01 UTC
A flaw was found in Moodle's URL downloader. Incorrect handling of IPv4-mapped IPv6 addresses in the host-blocking logic allows an authenticated user to bypass some blocked-host restrictions, resulting in a server-side request forgery (SSRF) risk when the downloader fetches a crafted URL. No further impact beyond partial blocklist bypass has been demonstrated.