{"api_version":"1","generated_at":"2026-04-23T02:14:25+00:00","cve":"CVE-2019-12520","urls":{"html":"https://cve.report/CVE-2019-12520","api":"https://cve.report/api/cve/CVE-2019-12520.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2019-12520","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2019-12520"},"summary":{"title":"CVE-2019-12520","description":"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. 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