CVE-2021-22903

描述

There is a possible Open Redirect Vulnerability in Action Pack. Versions Affected: >= v6.1.0.rc2 Not affected: < v6.1.0.rc2 Fixed Versions: 6.1.3.2 Impact ------ This is similar to CVE-2021-22881. Specially crafted Host headers in combination with certain "allowed host" formats can cause the Host Authorization middleware in Action Pack to redirect users to a malicious website. Since rails/rails@9bc7ea5, strings in config.hosts that do not have a leading dot are converted to regular expressions without proper escaping. This causes, for example, config.hosts << "sub.example.com" to permit a request with a Host header value of sub-example.com. Releases -------- The fixed releases are available at the normal locations. Workarounds ----------- The following monkey patch put in an initializer can be used as a workaround. ```ruby class ActionDispatch::HostAuthorization::Permissions def sanitize_string(host) if host.start_with?(".") /\A(.+\.)?#{Regexp.escape(host[1..-1])}\z/i else /\A#{Regexp.escape host}\z/i end end end ``` Patches ------- To aid users who aren't able to upgrade immediately we have provided patches for the two supported release series. They are in git-am format and consist of a single changeset. * 6-1-open-redirect.patch - Patch for 6.1 series Please note that only the 6.1.Z, 6.0.Z, and 5.2.Z series are supported at present. Users of earlier unsupported releases are advised to upgrade as soon as possible as we cannot guarantee the continued availability of security fixes for unsupported releases. Credits ------- Thanks Jonathan Hefner (https://hackerone.com/jonathanhefner) for reporting this bug!

如何修補 CVE-2021-22903

要修補 CVE-2021-22903,請將受影響套件升級到下列已修補版本。

• —升級至 6.1.3.2 或更新版本

CVE-2021-22903 正在被利用嗎?

低 — EPSS 為 0.1%,目前沒有觀察到大規模利用活動。

受影響套件(1)

• >= 6.1.0.rc2, < 6.1.3.2