CVE-2019-12520

描述

An issue was discovered in Squid through 4.7 and 5. When receiving a request, Squid checks its cache to see if it can serve up a response. It does this by making a MD5 hash of the absolute URL of the request. If found, it servers the request. The absolute URL can include the decoded UserInfo (username and password) for certain protocols. This decoded info is prepended to the domain. This allows an attacker to provide a username that has special characters to delimit the domain, and treat the rest of the URL as a path or query string. An attacker could first make a request to their domain using an encoded username, then when a request for the target domain comes in that decodes to the exact URL, it will serve the attacker's HTML instead of the real HTML. On Squid servers that also act as reverse proxies, this allows an attacker to gain access to features that only reverse proxies can use, such as ESI.

如何修補 CVE-2019-12520

要修補 CVE-2019-12520,請將受影響套件升級到下列已修補版本。

• —升級至 4.8-1 或更新版本

CVE-2019-12520 正在被利用嗎?

低 — EPSS 為 3.9%,目前沒有觀察到大規模利用活動。

受影響套件(1)

• from 0, < 4.8-1

CVSS 分數

參考連結(1)

• ADVISORYsecurity-tracker.debian.org/tracker/CVE-2019-12520