Security Bulletin: Potential SSL/TLS-related denial of service vulnerability in GSKit used with IBM Informix Client Software Development Kit (CSDK) (CVE-2013-6747)

Summary

An SSL/TLS connection initiated using a malformed certificate chain from a Client or Server could contain a circular reference. The circular reference can cause the chain building logic to loop and lead to an engine crash or an engine hang when it runs out of memory.

Vulnerability Details

CVSS:
CVE ID: CVE-2013-6747
CVSS Base Score: 7.1
CVSS Temporal Score: See <https://exchange.xforce.ibmcloud.com/vulnerabilities/89863&gt;[](&lt;https://exchange.xforce.ibmcloud.com/vulnerabilities/90723&gt;) for the current score
CVSS Environmental Score: Undefined:
CVSS Vector: (AV:N/AC:M/Au:N/C:N/I:N/A:C)

Affected Products and Versions

Informix Client SDK 4.10 or 3.70, using IBM GSKit version 8, up to 8.0.50.13
Informix Client SDK 3.50, using IBM GSKit version 7, up to 7.0.4.47

Remediation/Fixes

Product

| Remediation/First Fix
—|—
Informix Server 12.10| Upgrade to 12.10.xC3 or download and install GSKit (see next section)
Informix Server 11.70| Download and install the updated GSKit (see next section)
Informix Server 11.50| Download and install the updated GSKit (see next section)
Upgrading GSKit:

1. Download the appropriate GSKit using the following table:_ _
   Product |Required GSKit version|GSKit link
   —|—|—
   Informix Client SDK 4.10

Informix Client SDK 3.70 (all platforms other than HP-UX PA-RISC) | 8.0.50.17| AIX (pSeries_32, pSeries_64 ) HP-UX(Itanium_32, Itanium_64 ) Linux(x86_32, x86_64, pSeries_64, zSeries_32, zSeries_64) Solaris(SPARC_32, SPARC_64, x86_32, x86_64) Windows (x86_32, x86_64)
Informix Client SDK 3.70 (HP-UX PA-RISC platforms only) | 7.0.4.48| HP-UX (PA-RISC_32, PA-RISC_64)
Informix Client SDK 3.50 | 7.0.4.48| AIX (pSeries_32, pSeries_64) HP-UX(Itanium_32, Itanium_64, PA-RISC_32, PA-RISC_64) **Linux **(x86_32, x86_64, pSeries_64, zSeries_32, zSeries_64) **Solaris **(SPARC_32, SPARC_64, x86_32, x86_64) **Windows **(x86_32, x86_64)
2. Unix/Linux instructions: 1. Copy the downloaded tar file(s) to $INFORMIXDIR/gskit. Note: the old gskit .tar files must be removed or renamed to not end in .tar.
2. Bring the database server offline. (e.g. onmode -ky).
3. Change to the GSKit directory (cd $INFORMIXDIR/gskit).
4. As root, run “./installgskit”.
5. To verify the installation, run the appropriate command (i.e. gsk7ver, gsk7ver_64, gsk8ver or gsk8ver_64) for the GSKit you installed. The new version should be 7.0.4.48 or 8.0.50.17. 3. Windows GSkit version 7 x86_32 instructions: 1. Copy/download the gsk7d_7.0.4.48_win32.exe file to C:\tmp.
2. Start the ‘cmd’ program.
3. Change to the C:\temp directory (cd c:\tmp).
4. Run “gsk7d_7.0.4.48_win32.exe /D tmp”. This will extract the files to the C:\tmp\tmp directory.
5. Change to the C:\tmp\tmp directory (cd C:\tmp\tmp).
6. Run “setup GSK7BAS”. Accept all of the defaults.
7. To verify the installation, run gsk7ver to verify the installation. The new version should be 7.0.4.48. 4. All other Windows versions instructions: 1. Copy/download the appropriate file (gsk7d_7.0.4.48_win64.msi, gsk8ssl32.exe or gsk8ssl64.exe) to C:\tmp.
2. Using Windows Explorer, double click on the downloaded file. This will start Install Shield. Accept all of the defaults.
3. To verify the installation, run the appropriate command (i.e. gsk7ver_64, gsk8ver or gsk8ver_64) for the GSKit you installed. The new version should be 7.0.4.48 or 8.0.50.17.