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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-22245 Detail

Description

Mastodon is a free, open-source social network server based on ActivityPub. By nature, Mastodon performs a lot of outbound requests to user-provided domains. Mastodon, however, has some protection mechanism to disallow requests to local IP addresses (unless specified in `ALLOWED_PRIVATE_ADDRESSES`) to avoid the "confused deputy" problem. The list of disallowed IP address ranges was lacking some IP address ranges that can be used to reach local IP addresses. An attacker can use an IP address in the affected ranges to make Mastodon perform HTTP requests against loopback or local network hosts, potentially allowing access to otherwise private resources and services. This is fixed in Mastodon v4.5.4, v4.4.11, v4.3.17 and v4.2.29.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-B 7.1 HIGH
Vector:  CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/mastodon/mastodon/commit/0f4e8a6240b5af1f2c3f34d2793d8610c6ef2aca GitHub, Inc.
https://github.com/mastodon/mastodon/commit/17022907866710a72a1b1fc0a5ce9538bad1b4c3 GitHub, Inc.
https://github.com/mastodon/mastodon/commit/71ae4cf2cf5138ccdda64b1b1d665849b688686d GitHub, Inc.
https://github.com/mastodon/mastodon/security/advisories/GHSA-xfrj-c749-jxxq GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-918 Server-Side Request Forgery (SSRF) GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-22245
NVD Published Date:
01/08/2026
NVD Last Modified:
01/08/2026
Source:
GitHub, Inc.