Multiple vendor SSL intermediate CA-signed certificate spoofing

ssl-ca-certificate-spoofing (9776) The risk level is classified as HighHigh Risk

Description:

A vulnerability in multiple vendor's handling of SSL certificates could allow a remote attacker to spoof an intermediate CA-signed (Certificate Authority) certificate and perform a man-in-the-middle attack against an unsuspecting user. This vulnerability is caused by improper verification of the Basic Constraints field when validating intermediate CA-signed certificates. An attacker could use this vulnerability to spoof trusted Web sites, digitally signed emails, certificate-based authentication, and Authenticode signatures.


Consequences:

Bypass Security

Remedy:

Apply the appropriate patch for your system, as listed in Microsoft Security Bulletin MS02-050. See References.

For Windows NT:
Microsoft originally provided a patch for this vulnerability in MS02-050, but it has been superseded by the patch released with MS04-011. See References.

For TinySSL:
Upgrade to the latest version of TinySSL (1.03 or later), available from the TinySSL Web site. See References.

For KDE:
Upgrade to the latest version of KDE (3.0.3 or later), as listed in KDE Security Advisory: Konqueror SSL vulnerability. See References.

For Mandrake Linux:
Upgrade to the latest kdelibs package, as listed below. Refer to MandrakeSoft Security Advisory MDKSA-2002:058 : kdelibs for more information. See References.

Mandrake Linux 8.1 and 8.1(IA64): 2.2.1-5.2mdk or later
Mandrake Linux 8.1 and 8.1(IA64): 2.2.2-48.1mdk or later

— OR —

Apply the patch for this vulnerability, as listed in KDE Security Advisory: Konqueror SSL vulnerability. See References.

For Conectiva Linux 8.0:
Upgrade to the latest KDE package (3.0.3-1U80_1cl or later), available from the Conectiva Linux Security Announcement CLSA-2002:519. See References

For FreeBSD Ports Collection:
Upgrade to the latest ports collection, as listed in FreeBSD Security Notice FreeBSD-SN-02:05. See References.

For Red Hat Linux:
Upgrade to the latest kde package, as listed below. Refer to Red Hat Security Advisory RHSA-2002:220-40 for more information. See References.

Red Hat Linux 7.2: 2.2.2-3 or later
Red Hat Linux 7.3: 1.0.3-0.7.1 or later

For other distributions:
Contact your vendor for upgrade or patch information.

References:

  • BugTraq Mailing List, Mon Aug 05 2002 - 18:03:29 CDT : IE SSL Vulnerability .
  • BugTraq Mailing List, Mon Aug 19 2002 - 09:40:41 CDT : Insufficient Verification of Client Certificates in IIS 5.0 pre sp3 .
  • BugTraq Mailing List, Sat Aug 10 2002 - 22:28:25 CDT: TinySSL Vendor Statement: Basic Constraints Vulnerability.
  • CIAC Information Bulletin M-121: Microsoft Certificate Validation Vulnerability.
  • CIAC Information Bulletin N-020: Red Hat Multiple Vulnerabilities in KDE.
  • Conectiva Linux Announcement CLSA-2002:519: kde.
  • FreeBSD Security Notice FreeBSD-SN-02:05 : security issues in ports.
  • KDE Security Advisory 2002-08-18: Konqueror SSL vulnerability.
  • Microsoft Corporation Web site: Information about Reported Web Security Vulnerability August 2002.
  • Microsoft Security Bulletin MS02-050: Certificate Validation Flaw Could Enable Identity Spoofing (Q328145).
  • Microsoft Security Bulletin MS04-011: Security Update for Microsoft Windows (835732).
  • Moxie Marlinspike Whitepaper: New Tricks For Defeating SSL In Practice.
  • TinySSL Web site: TinySSL -- A Lightweight SSL Implementation in Java.
  • VulnWatch Mailing List, Wed Jan 22 2003 - 02:54:35 CST: IE chain vulnerability.
  • BID-33837: Mozilla Firefox International Domain Name Subdomain URI Spoofing Vulnerability
  • BID-5410: Multiple Vendor Invalid X.509 Certificate Chain Vulnerability
  • CVE-2002-0828: ** REJECT ** DO NOT USE THIS CANDIDATE NUMBER. ConsultIDs: CVE-2002-0862. Reason: This is a duplicate of CVE-2002-0862. Notes: All CVE users should reference CVE-2002-0862 instead of this candidate. All references and descriptions in this candidate have been removed to prevent accidental usage.
  • CVE-2002-0862: The (1) CertGetCertificateChain, (2) CertVerifyCertificateChainPolicy, and (3) WinVerifyTrust APIs within the CryptoAPI for Microsoft products including Microsoft Windows 98 through XP, Office for Mac, Internet Explorer for Mac, and Outlook Express for Mac, do not properly verify the Basic Constraints of intermediate CA-signed X.509 certificates, which allows remote attackers to spoof the certificates of trusted sites via a man-in-the-middle attack for SSL sessions, as originally reported for Internet Explorer and IIS.
  • CVE-2002-0970: The SSL capability for Konqueror in KDE 3.0.2 and earlier does not verify the Basic Constraints for an intermediate CA-signed certificate, which allows remote attackers to spoof the certificates of trusted sites via a man-in-the-middle attack.
  • CVE-2002-1183: Microsoft Windows 98 and Windows NT 4.0 do not properly verify the Basic Constraints of digital certificates, allowing remote attackers to execute code, aka New Variant of Certificate Validation Flaw Could Enable Identity Spoofing (CAN-2002-0862).
  • CVE-2002-1407: TinySSL 1.02 and earlier does not verify the Basic Constraints for an intermediate CA-signed certificate, which allows remote attackers to spoof the certificates of trusted sites via a man-in-the-middle attack.
  • CVE-2009-0653: OpenSSL, probably 0.9.6, does not verify the Basic Constraints for an intermediate CA-signed certificate, which allows remote attackers to spoof the certificates of trusted sites via a man-in-the-middle attack, a related issue to CVE-2002-0970.
  • DSA-155: kdelibs -- privacy escalation with Konqueror
  • MDKSA-2002:058: Updated kdelibs packages fix SSL vulnerability
  • OSVDB ID: 59725: TinySSL SSL Basic Constraints Intermediate CA-signed Certificate Validation Failure
  • OSVDB ID: 865: Multiple Vendor SSL Basic Constraints Intermediate CA-signed Certificate Validation Failure
  • RHSA-2002-220: Updated KDE packages fix security issues
  • RHSA-2002-221: kdelibs security update

Platforms Affected:

  • Adam Megacz TinySSL 1.02
  • Conectiva Linux 8.0
  • Debian Debian Linux 3.0
  • FreeBSD FreeBSD Ports Collection
  • KDE KDE 3.0.2
  • MandrakeSoft Mandrake Linux 8.1
  • MandrakeSoft Mandrake Linux 8.2
  • Microsoft Internet Explorer
  • Microsoft Office 2001
  • Microsoft Office 98 Mac OS
  • Microsoft Outlook Express Mac OS
  • Microsoft Windows NT 4.0 Terminal Server
  • RedHat Enterprise Linux 2.1 AS
  • RedHat Linux 7.2
  • RedHat Linux 7.3
  • RedHat Linux 8.0
  • Various vendors RADIUS

Reported:

Aug 05, 2002

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