id: CVE-2021-38751 info: name: ExponentCMS <= 2.6 - Host Header Injection author: dwisiswant0 severity: medium description: An HTTP Host header attack exists in ExponentCMS 2.6 and below in /exponent_constants.php. A modified HTTP header can change links on the webpage to an arbitrary value,leading to a possible attack vector for MITM. impact: | An attacker can manipulate the Host header to perform various attacks, including phishing, session hijacking, and cache poisoning. remediation: | Upgrade ExponentCMS to a version higher than 2.6 or apply the provided patch to fix the Host Header Injection vulnerability. reference: - https://nvd.nist.gov/vuln/detail/CVE-2021-38751 - https://github.com/exponentcms/exponent-cms/issues/1544 - https://github.com/exponentcms/exponent-cms/blob/a9fa9358c5e8dc2ce7ad61d7d5bea38505b8515c/exponent_constants.php#L56-L64 classification: cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N cvss-score: 4.3 cve-id: CVE-2021-38751 cwe-id: CWE-116 epss-score: 0.00242 epss-percentile: 0.62095 cpe: cpe:2.3:a:exponentcms:exponentcms:*:*:*:*:*:*:*:* metadata: max-request: 1 vendor: exponentcms product: exponentcms tags: cve2021,cve,exponentcms http: - method: GET path: - "{{BaseURL}}" headers: Host: '{{randstr}}.tld' matchers-condition: and matchers: - type: word part: body words: - '{{randstr}}.tld' - 'EXPONENT.PATH' - 'EXPONENT.URL' condition: and - type: status status: - 200 # digest: 4b0a00483046022100d403330f10efac52c9115d6f86b8203afbd89a11548fcabd8cbb223b1901297b022100f557cc58343805a3b938dfc6b41aa4bdc6656b57ac2bfad9ed9eab9f15359a89:922c64590222798bb761d5b6d8e72950