CVE-2026-72916
MEDIUM
6,3
Source: [email protected]
Attack Vector: network
Attack Complexity: high
Privileges Required: none
User Interaction: none
Confidentiality: N/A
Integrity: N/A
Availability: N/A
Description
AI Translation Available
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.
918
Server-Side Request Forgery (SSRF)
IncompleteCommon Consequences
Security Scopes Affected:
Confidentiality
Integrity
Access Control
Potential Impacts:
Read Application Data
Execute Unauthorized Code Or Commands
Bypass Protection Mechanism
Applicable Platforms
Technologies:
Web Based, AI/ML, Web Server
1286
Improper Validation of Syntactic Correctness of Input
IncompleteCommon Consequences
Security Scopes Affected:
Other
Potential Impacts:
Varies By Context
Applicable Platforms
All platforms may be affected
https://github.com/mastodon/mastodon/commit/18c61f286f1f5718a8f517940ba384866ff…
https://github.com/mastodon/mastodon/commit/467c933459c7d0e5513475b9e4888afaedf…
https://github.com/mastodon/mastodon/commit/930aa9fee26bf9eaefe27826fa1061288d8…
https://github.com/mastodon/mastodon/commit/da47a1bd3cd07935d7ca55a1f4f1a76f7f1…
https://github.com/mastodon/mastodon/releases/tag/v4.4.21
https://github.com/mastodon/mastodon/releases/tag/v4.5.14
https://github.com/mastodon/mastodon/releases/tag/v4.6.4
https://github.com/mastodon/mastodon/releases/tag/v4.7.0-beta.1
https://github.com/mastodon/mastodon/security/advisories/GHSA-vwhj-3g83-v276