CVE-2026-27477

描述

Mastodon is a free, open-source social network server based on ActivityPub. FASP registration requires manual approval by an administrator. In versions 4.4.0 through 4.4.13 and 4.5.0 through 4.5.6, an unauthenticated attacker can register a FASP with an attacker-chosen `base_url` that includes or resolves to a local / internal address, leading to the Mastodon server making requests to that address. This only affects Mastodon servers that have opted in to testing the experimental FASP feature by setting the environment variable `EXPERIMENTAL_FEATURES` to a value including `fasp`. An attacker can force the Mastodon server to make http(s) requests to internal systems. While they cannot control the full URL that is being requested (only the prefix) and cannot see the result of those requests, vulnerabilities or other undesired behavior could be triggered in those systems. The fix is included in the 4.4.14 and 4.5.7 releases. Admins that are actively testing the experimental "fasp" feature should update their systems. Servers not using the experimental feature flag `fasp` are not affected.

如何修補 CVE-2026-27477

要修補 CVE-2026-27477,請將受影響套件升級到下列已修補版本。

• —升級至 4.4.14 或更新版本

CVE-2026-27477 正在被利用嗎?

低 — EPSS 為 0.3%,目前沒有觀察到大規模利用活動。

受影響套件(1)

• >= 4.4.0, < 4.4.14, >= 4.5.0, < 4.5.7

CVSS 分數

參考連結(3)

• WEBgithub.com/mastodon/mastodon/commit/7b85d2182361e68d51d9a02f94fb1070b5f503b1
• WEBgithub.com/mastodon/mastodon/security/advisories/GHSA-46w6-g98f-wxqm
• WEBnvd.nist.gov/vuln/detail/CVE-2026-27477