CVE-2026-72916

See a problem?
Please try reporting it to the source first.
Source
https://cve.org/CVERecord?id=CVE-2026-72916
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72916.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-72916
Aliases
Published
2026-08-10T21:19:02Z
Modified
2026-10-28T02:30:52Z
Severity
  • 6.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:L CVSS Calculator
Summary
Mastodon: SSRF Protection Bypass via IPv4-compatible IPv6 Addresses
Details

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.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-1286",
        "CWE-918"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72916.json"
}
References

Affected packages

Git / github.com/mastodon/mastodon

Affected ranges

Type
GIT
Repo
https://github.com/mastodon/mastodon
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
da47a1bd3cd07935d7ca55a1f4f1a76f7f167e0d
Introduced
5a8ab0a3e62a8825e28bb74c1760ba6488d20c97
Fixed
18c61f286f1f5718a8f517940ba384866ffa3892
Introduced
52aa8a44bbd0c9a6673cbd9b7c088020be938799
Fixed
930aa9fee26bf9eaefe27826fa1061288d83373b
Fixed
467c933459c7d0e5513475b9e4888afaedfb1074
Fixed
827f63a8fe976e07921ab0f5c9fcca8420c56858
Database specific
Show details 
{
    "extracted_events": [
        {
            "range": [
                {
                    "introduced": "0"
                },
                {
                    "fixed": "4.4.21"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StringRangeExpression"
        },
        {
            "range": [
                {
                    "introduced": "4.5.0-beta.1"
                },
                {
                    "fixed": "4.5.14"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StringRangeExpression"
        },
        {
            "range": [
                {
                    "introduced": "4.6.0-beta.1"
                },
                {
                    "fixed": "4.6.4"
                }
            ],
            "source": "AFFECTED_FIELD",
            "strategy": "StringRangeExpression"
        },
        {
            "range": [
                {
                    "fixed": "18c61f286f1f5718a8f517940ba384866ffa3892"
                }
            ],
            "source": "REFERENCES_COMMIT"
        },
        {
            "range": [
                {
                    "fixed": "467c933459c7d0e5513475b9e4888afaedfb1074"
                }
            ],
            "source": "REFERENCES_COMMIT"
        },
        {
            "range": [
                {
                    "fixed": "930aa9fee26bf9eaefe27826fa1061288d83373b"
                }
            ],
            "source": "REFERENCES_COMMIT"
        },
        {
            "range": [
                {
                    "fixed": "da47a1bd3cd07935d7ca55a1f4f1a76f7f167e0d"
                }
            ],
            "source": "REFERENCES_COMMIT"
        },
        {
            "original_tag": "v4.4.21",
            "range": [
                {
                    "fixed": "da47a1bd3cd07935d7ca55a1f4f1a76f7f167e0d"
                }
            ],
            "source": "REFERENCES_TAG"
        },
        {
            "original_tag": "v4.5.14",
            "range": [
                {
                    "fixed": "18c61f286f1f5718a8f517940ba384866ffa3892"
                }
            ],
            "source": "REFERENCES_TAG"
        },
        {
            "original_tag": "v4.6.4",
            "range": [
                {
                    "fixed": "930aa9fee26bf9eaefe27826fa1061288d83373b"
                }
            ],
            "source": "REFERENCES_TAG"
        },
        {
            "original_tag": "v4.7.0-beta.1",
            "range": [
                {
                    "fixed": "827f63a8fe976e07921ab0f5c9fcca8420c56858"
                }
            ],
            "source": "REFERENCES_TAG"
        }
    ]
}

Affected versions

v0.*
v0.1.0
v0.1.1
v0.1.2
v0.6
v0.7
v0.8
v0.9
v0.9.9
v1.*
v1.0
v1.1
v1.1.1
v1.1.2
v1.2
v1.2.1
v1.2.2
v1.3
v1.3.1
v1.3.2
v1.4.1
v1.4.2
v1.4.3
v1.4.4
v1.4.5
v1.4.6
v1.4.7
v1.4rc1
v1.4rc2
v1.4rc3
v1.4rc4
v1.4rc5
v1.4rc6
v1.5.0
v1.5.0rc1
v1.5.0rc2
v1.5.0rc3
v1.5.1
v1.6.0
v1.6.0rc1
v1.6.0rc2
v1.6.0rc3
v1.6.0rc4
v1.6.0rc5
v1.6.1
v2.*
v2.0.0
v2.0.0rc1
v2.0.0rc2
v2.0.0rc3
v2.0.0rc4
v2.1.0
v2.1.0rc1
v2.1.0rc2
v2.1.0rc3
v2.1.0rc4
v2.1.0rc5
v2.1.0rc6
v2.1.1
v2.1.2
v2.1.3
v2.2.0
v2.2.0rc1
v2.2.0rc2
v2.3.0
v2.3.0rc1
v2.3.0rc2
v2.3.0rc3
v2.3.1
v2.3.1rc1
v2.3.1rc2
v2.3.1rc3
v2.3.2
v2.3.2rc1
v2.3.2rc2
v2.3.2rc3
v2.3.2rc4
v2.3.2rc5
v2.4.0
v2.4.0rc1
v2.4.0rc2
v2.4.0rc3
v2.4.0rc4
v2.4.0rc5
v2.4.1
v2.4.1rc1
v2.4.1rc2
v2.4.1rc3
v2.4.1rc4
v2.4.2
v2.4.2rc1
v2.4.2rc2
v2.4.2rc3
v2.4.3
v2.4.3rc1
v2.4.3rc2
v2.4.3rc3
v2.5.0
v2.5.0rc1
v2.5.0rc2
v2.6.0
v2.6.0rc1
v2.6.0rc2
v2.6.0rc3
v2.6.0rc4
v2.6.1
v2.7.0
v2.7.0rc1
v2.7.0rc2
v2.7.0rc3
v2.7.1
v2.8.0
v2.8.0rc1
v2.8.0rc2
v2.8.0rc3
v2.8.1
v2.8.2
v2.9.0
v2.9.0rc1
v2.9.0rc2
v2.9.1
v2.9.2
v3.*
v3.0.0
v3.0.0rc1
v3.0.0rc2
v3.0.0rc3
v3.0.1
v3.1.0
v3.1.0rc1
v3.1.0rc2
v3.1.1
v3.1.2
v3.1.3
v3.1.4
v3.2.0
v3.2.0rc1
v3.2.0rc2
v3.3.0
v3.3.0rc1
v3.3.0rc2
v3.3.0rc3
v3.4.0
v3.4.0rc1
v3.4.0rc2
v3.4.1
v3.5.0
v3.5.0rc1
v3.5.0rc2
v3.5.0rc3
v3.5.1
v3.5.2
v3.5.3
v4.*
v4.0.0
v4.0.0rc1
v4.0.0rc2
v4.0.0rc3
v4.0.0rc4
v4.0.1
v4.0.2
v4.1.0
v4.1.0rc1
v4.1.0rc2
v4.1.0rc3
v4.2.0
v4.2.0-beta1
v4.2.0-beta2
v4.2.0-beta3
v4.2.0-rc1
v4.2.0-rc2
v4.3.0-beta.1
v4.3.0-beta.2
v4.3.0-rc.1
v4.4.0
v4.4.0-beta.1
v4.4.0-beta.2
v4.4.0-rc.1
v4.4.1
v4.4.10
v4.4.11
v4.4.12
v4.4.13
v4.4.14
v4.4.15
v4.4.16
v4.4.17
v4.4.18
v4.4.19
v4.4.2
v4.4.20
v4.4.3
v4.4.4
v4.4.5
v4.4.6
v4.4.7
v4.4.8
v4.4.9
v4.5.0
v4.5.0-beta.1
v4.5.0-beta.2
v4.5.0-rc.1
v4.5.0-rc.2
v4.5.0-rc.3
v4.5.1
v4.5.10
v4.5.11
v4.5.12
v4.5.13
v4.5.2
v4.5.3
v4.5.4
v4.5.5
v4.5.6
v4.5.7
v4.5.8
v4.5.9
v4.6.0
v4.6.0-beta.1
v4.6.0-rc.1
v4.6.0-rc.2
v4.6.1
v4.6.2
v4.6.3

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72916.json"