IBM SECURITY ADVISORY First Issued: Fri Feb 21 09:27:21 CST 2020 The most recent version of this document is available here: http://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory2.asc https://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory2.asc ftp://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory2.asc Security Bulletin: Vulnerabilities in Curl affect PowerSC (CVE-2019-5481, CVE-2019-5482) =============================================================================== SUMMARY: There are vulnerabilities in Curl that affect PowerSC. =============================================================================== VULNERABILITY DETAILS: CVEID: CVE-2019-5481 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-5481 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-5481 DESCRIPTION: cURL libcurl is vulnerable to a denial of service, caused by a double free flaw during kerberos FTP data transfer. By sending a specially-crafted size of data, a remote attacker could exploit this vulnerability to cause a denial of service condition. CVSS Base score: 5.3 CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/166941 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) CVEID: CVE-2019-5482 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-5482 https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-5482 DESCRIPTION: cURL libcurl is vulnerable to a heap-based buffer overflow, caused by improper bounds checking by the tftp_receive_packet function. By sending specially-crafted request containing an OACK without the BLKSIZE option, a remote attacker could overflow a buffer and execute arbitrary code on the system. CVSS Base score: 6.3 CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/166942 for the current score. CVSS Vector: (CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L) AFFECTED PRODUCTS AND VERSIONS: PowerSC 1.2 PowerSC 1.3 The vulnerabilities in the following filesets are being addressed: key_fileset = powerscStd.tnc_pm key_fileset = curl-7.67.0-1.aix6.1.ppc.rpm Fileset Lower Level Upper Level KEY --------------------------------------------------------------- powerscStd.tnc_pm 1.2.0.3 1.3.0.0 key_w_fs curl-7.67.0-1.aix6.1.ppc.rpm 7.19.4 7.65.3 key_w_fs 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: 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_fix2.tar http://aix.software.ibm.com/aix/efixes/powersc/security/curl_fix2.tar https://aix.software.ibm.com/aix/efixes/powersc/security/curl_fix2.tar 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_fix2.tar cd curl_fix2 Verify you have retrieved the fixes intact: The checksums below were generated using the "openssl dgst -sha256 " command as the following: openssl dgst -sha256 filename KEY -------------------------------------------------------------------------------------------------------------- 67205f3ea486ef9a65246ba7d97b0635fe66fdfab04560ea76bc9d9b4e7fbf04 curl-7.67.0-1.aix6.1.ppc.rpm key_w_csum dc8c6c00cd6c0238a9e56f52135955b9b91404c3632af208248a5efc4737efd6 krb5-libs-1.16.1-3.aix6.1.ppc.rpm key_w_csum 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 -signature .sig openssl dgst -sha1 -verify -signature .sig Published advisory OpenSSL signature file location: http://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory2.asc.sig https://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory2.asc.sig ftp://aix.software.ibm.com/aix/efixes/powersc/security/curl_advisory2.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_fix2.tar cd curl_fix2 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. =============================================================================== CONTACT US: Note: Keywords labeled as KEY in this document are used for parsing purposes. If you would like to receive PowerSC Security Advisories via email, please visit "My Notifications": http://www.ibm.com/support/mynotifications https://www.ibm.com/support/mynotifications To view previously issued advisories, please visit: http://www14.software.ibm.com/webapp/set2/subscriptions/onvdq https://www14.software.ibm.com/webapp/set2/subscriptions/onvdq Contact IBM Support for questions related to this announcement: http://ibm.com/support/ https://ibm.com/support/ To obtain the OpenSSL public key that can be used to verify the signed advisories and ifixes: Download the key from our web page: http://www.ibm.com/systems/resources/systems_p_os_aix_security_pubkey.txt https://www.ibm.com/systems/resources/systems_p_os_aix_security_pubkey.txt Please contact your local IBM AIX support center for any assistance. REFERENCES: Complete CVSS v3 Guide: http://www.first.org/cvss/user-guide https://www.first.org/cvss/user-guide On-line Calculator v3: http://www.first.org/cvss/calculator/3.0 https://www.first.org/cvss/calculator/3.0 ACKNOWLEDGEMENTS: None. CHANGE HISTORY: First Issued: Fri Feb 21 09:27:21 CST 2020 =============================================================================== *The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin. Disclaimer According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES "AS IS" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.