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CVE-2026-72916 Details

UNDERGOING ENRICHMENT

The CVE is currently being enriched by the Volerion team. The enrichment process results in the association of reference link tags, CVSS, and CPE applicability statement data.

Description

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.4.21, 4.5.14, 4.6.4, and 4.7.0-beta.1, PrivateAddressCheck.private_address? in app/lib/private_address_check.rb normalized IPv4-mapped IPv6 addresses but did not recognize IPv4-compatible IPv6 addresses with IPAddr#ipv4_compat?. An attacker could supply an address in the omitted range to bypass the ALLOWED_PRIVATE_ADDRESSES protection and make Mastodon send HTTP requests to loopback interfaces, potentially accessing private resources and services. Exploitation requires a system that supports the obsolete IPv4-compatible IPv6 mechanism. This issue is fixed in versions 4.4.21, 4.5.14, 4.6.4, and 4.7.0-beta.1.

Metrics

CVSS 3.x Severity and Vector Strings:

VolerionCVSS-B:…Vector:This vulnerability is currently being analyzed.

No CVSS 3.x data is available for this CVE.

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.

URL	Source(s)	Tag(s)
https://github.com/mastodon/mastodon/commit/18c61f286f1f5718a8f517940ba384866ffa3892	[email protected]
https://github.com/mastodon/mastodon/commit/467c933459c7d0e5513475b9e4888afaedfb1074	[email protected]
https://github.com/mastodon/mastodon/commit/930aa9fee26bf9eaefe27826fa1061288d83373b	[email protected]
https://github.com/mastodon/mastodon/commit/da47a1bd3cd07935d7ca55a1f4f1a76f7f167e0d	[email protected]
https://github.com/mastodon/mastodon/releases/tag/v4.4.21	[email protected]
https://github.com/mastodon/mastodon/releases/tag/v4.5.14	[email protected]
https://github.com/mastodon/mastodon/releases/tag/v4.6.4	[email protected]
https://github.com/mastodon/mastodon/releases/tag/v4.7.0-beta.1	[email protected]
https://github.com/mastodon/mastodon/security/advisories/GHSA-vwhj-3g83-v276	[email protected]

see all 9 references

Weakness Enumeration

CWE-ID	CWE Name	Source
CWE-1286	Improper Validation of Syntactic Correctness of Input	[email protected]
CWE-918	Server-Side Request Forgery (SSRF)	[email protected]

Affected Products

This vulnerability is currently being analyzed

Change History

2 change records found show changes

Date	Action	Recorded By
Aug 13, 2026	CVE Modified	CISA-ADP
Aug 10, 2026	New CVE Received	[email protected]