Security Bulletin: Vulnerability in Curl affects PowerSC (CVE-2020-8231)

Summary

There is a vulnerability in Curl that affects PowerSC.

Vulnerability Details

CVEID:CVE-2020-8231
**DESCRIPTION:**cURL libcurl could allow a remote attacker to obtain sensitive information, caused by the improper handling of the CURLOPT_CONNECT_ONLY option. The raw data is sent over that connection to the wrong destination. An attacker could exploit this vulnerability to obtain sensitive information.
CVSS Base score: 5.3
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/186954 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)

Affected Products and Versions

The vulnerabilities in the following filesets are being addressed:

Note: To find out whether the affected PowerSC filesets are installed on your systems, refer to the lslpp command found in AIX user’s guide. To find out whether the affected curl filesets are installed on your systems, refer to the rpm command found in AIX user’s guide.

Example: lslpp -l | grep powerscStd

Example: rpm -qa | grep curl

Remediation/Fixes

A. FIXES

Fixes are available.

The fixes can be downloaded via ftp or http from:

ftp://aix.software.ibm.com/aix/efixes/powersc/security/curl_fix4.tar

<http://aix.software.ibm.com/aix/efixes/powersc/security/curl_fix4.tar&gt;

<https://aix.software.ibm.com/aix/efixes/powersc/security/curl_fix4.tar&gt;

The link above is to a tar file containing this signed advisory, open source fix packages, and OpenSSL signatures for each package.

To extract the fixes from the tar file:

tar xvf curl_fix4.tar

cd curl_fix4

Verify you have retrieved the fixes intact:

The checksums below were generated using the “openssl dgst -sha256 [filename]” command as the following:

openssl dgst -sha256

| filename
—|—

2ca1bcb4bb5f05c8ff50b60589c36ac70da5b368495e61e239d05da2bb7dddef

|

curl-7.72.0-1.aix6.1.ppc.rpm

afc18de14b96962c23cd914f4d8d4d6ecc1be73c1c46809a8ee6dddfbc8e06ca

|

libgcc-8.3.0-3.aix7.2.ppc.rpm

These sums should match exactly. The OpenSSL signatures in the tar file and on this advisory can also be used to verify the integrity of the fixes. If the sums or signatures cannot be confirmed, contact IBM Support.

openssl dgst -sha1 -verify <pubkey_file> -signature <advisory_file>.sig <advisory_file>

openssl dgst -sha1 -verify <pubkey_file> -signature <ifix_file>.sig <ifix_file>

Published advisory OpenSSL signature file location:

<http://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory4.asc.sig&gt;

<https://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory4.asc.sig&gt;

ftp://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory4.asc.sig

B. FIX AND INTERIM FIX INSTALLATION

IMPORTANT: If possible, it is recommended that a mksysb backup of the system be created. Verify it is both bootable and readable before proceeding.

To extract the fixes from the tar file:

tar xvf curl_fix4.tar

cd curl_fix4

To install a fix package:

rpm -ivh *.rpm

rpm -Uvh *.rpm

Interim fixes have had limited functional and regression testing but not the full regression testing that takes place for Service Packs; however, IBM does fully support them.

Workarounds and Mitigations

None