Security Bulletin: Multiple vulnerabilities in Curl affect PowerSC

Summary

There are multiple vulnerabilities in Curl that affect PowerSC.

Vulnerability Details

CVEID:CVE-2022-32206
**DESCRIPTION:**cURL libcurl is vulnerable to a denial of service, caused by a flaw in the number of acceptable “links” in the “chained” HTTP compression algorithms. By persuading a victim to connect a specially-crafted server, a remote attacker could exploit this vulnerability to insert a virtually unlimited number of compression steps, and results in a denial of service condition.
CVSS Base score: 4.3
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/229740 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L)

CVEID:CVE-2022-32207
**DESCRIPTION:**cURL libcurl could allow a remote attacker to obtain sensitive information, caused by improper preservation of permissions when saving cookies, alt-svc and hsts data to local files. By sending a specially-crafted request, an attacker could exploit this vulnerability to obtain sensitive information, and use this information to launch further attacks against the affected system.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/229741 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N)

CVEID:CVE-2022-32208
**DESCRIPTION:**cURL libcurl is vulnerable to a man-in-the-middle attack, caused by a flaw in the handling of message verification failures. An attacker could exploit this vulnerability to launch a man-in-the-middle attack and gain access to the communication channel between endpoints to inject data to the client…
CVSS Base score: 3.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/229742 for the current score.
CVSS Vector: (CVSS:3.0/AV:A/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N)

CVEID:CVE-2022-32205
**DESCRIPTION:**cURL libcurl is vulnerable to a denial of service, caused by an issue with the ability to set excessive amounts of Set-Cookie: headers in a HTTP response to curl by a server. By persuading a victim to connect a specially-crafted server, a remote attacker could exploit this vulnerability to create requests that become larger than the threshold, and results in a denial of service condition.
CVSS Base score: 4.3
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/229739 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L)

CVEID:CVE-2022-35252
**DESCRIPTION:**cURL libcurl is vulnerable to a denial of service, caused by a flaw when cookies contain control codes are later sent back to an HTTP(S) server. By sending a specially-crafted request, a remote attacker could exploit this vulnerability to cause a “sister site” to deny service to siblings.
CVSS Base score: 5.3
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/234980 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)

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

IBM highly recommends addressing the vulnerabilities now.

The fixes can be downloaded via ftp or http from:

ftp://aix.software.ibm.com/aix/efixes/powersc/security/curl_fix9.tar

<http://aix.software.ibm.com/aix/efixes/powersc/security/curl_fix9.tar&gt;

<https://aix.software.ibm.com/aix/efixes/powersc/security/curl_fix9.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_fix9.tar

cd curl_fix9

Verify you have retrieved the fixes intact:

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

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 -sha256 -verify [pubkey_file] -signature [advisory_file].sig [advisory_file]

openssl dgst -sha256 -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_advisory9.asc.sig&gt;

<https://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory9.asc.sig&gt;

ftp://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory9.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_fix9.tar

cd curl_fix9

To install a fix package:

rpm -ivh *.rpm

rpm -Uvh *.rpm

To install any dependencies along with the fix package:

yum update curl

Workarounds and Mitigations

None