Internet Explorer vulnerable in handling CDO protocol


Internet Explorer is vulnerable in handling CDO (Collaboration Data Objects) protocol, which allows the download dialog box to be bypassed.

When Internet Explorer (IE) accesses a website using CDO (Collaboration Data Objects), IE processes the contents as CDO data, ignoring their actual content types, and IE does not properly handle the Content-Disposition header field.
This could cause a download dialog box not to be displayed prior to downloading. The CDO protocol handler is included in an Office component, and Microsoft provides the fix for this component.

NetAgent Co., Ltd. reported this vulnerability to IPA.
JPCERT/CC coordinated with the Microsoft Corporation under Information Security Early Warning Partnership.
CVSS Severity (What is CVSS?)

CVSS V2 Severity:
Base Metrics 2.6 (Low) [IPA Score]
  • Access Vector: Network
  • Access Complexity: High
  • Authentication: None
  • Confidentiality Impact: None
  • Integrity Impact: Partial
  • Availability Impact: None
Affected Products

Microsoft Corporation
  • Microsoft Office xp Service Pack 3


An arbitrary script could be executed without explicit user consent, as the download dialog box is not displayed on the user's IE.

[Update the Software]
Update to the latest version according to the information provided by the vendor.
Vendor Information

Microsoft Corporation
  • Microsoft Security Bulletin : MS08-056
CWE (What is CWE?)

  1. No Mapping(CWE-Other) [IPA Evaluation]
CVE (What is CVE?)

  1. CVE-2008-4020

  1. JVN : JVN#55410403
  2. National Vulnerability Database (NVD) : CVE-2008-4020
  3. US-CERT Cyber Security Alerts : SA08-288A
  4. US-CERT Technical Cyber Security Alert : TA08-288A
  5. Secunia Advisory : SA32138
  6. SecurityFocus : 31693
  7. FrSIRT Advisories : FrSIRT/ADV-2008-2807
  8. JVN iPedia (Japanese) : JVNDB-2008-000070
Revision History

  • [2008/10/22]
      Web page published