Security Bulletin
Summary
The updates indicated below have been released to address the following vulnerabilities: OpenSSL vulnerabilites - CVE-2019-1559, CVE-2018-0734 Linux Kernel vulnerabilites - CVE-2019-11477, CVE-2019-11478 and CVE-2019-11479
Vulnerability Details
DESCRIPTION: If an application encounters a fatal protocol error and then calls SSL_shutdown() twice (once to send a close_notify, and once to receive one) then OpenSSL can respond differently to the calling application if a 0 byte record is received with invalid padding compared to if a 0 byte record is received with an invalid MAC. If the application then behaves differently based on that in a way that is detectable to the remote peer, then this amounts to a padding oracle that could be used to decrypt data. In order for this to be exploitable "non-stitched" ciphersuites must be in use. Stitched ciphersuites are optimised implementations of certain commonly used ciphersuites. Also the application must call SSL_shutdown() twice even if a protocol error has occurred (applications should not do this but some do anyway). Fixed in OpenSSL 1.0.2r (Affected 1.0.2-1.0.2q).
CVSS Base score: 5.8
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/157514 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N)
CVEID: CVE-2018-0734
DESCRIPTION: The OpenSSL DSA signature algorithm has been shown to be vulnerable to a timing side channel attack. An attacker could use variations in the signing algorithm to recover the private key. Fixed in OpenSSL 1.1.1a (Affected 1.1.1). Fixed in OpenSSL 1.1.0j (Affected 1.1.0-1.1.0i). Fixed in OpenSSL 1.0.2q (Affected 1.0.2-1.0.2p).
CVSS Base score: 3.7
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/152085 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N)
CVEID: CVE-2019-11479
DESCRIPTION: Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commits 967c05aee439e6e5d7d805e195b3a20ef5c433d6 and 5f3e2bf008c2221478101ee72f5cb4654b9fc363.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/162665 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
CVEID: CVE-2019-11477
DESCRIPTION: Jonathan Looney discovered that the TCP_SKB_CB(skb)->tcp_gso_segs value was subject to an integer overflow in the Linux kernel when handling TCP Selective Acknowledgments (SACKs). A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit 3b4929f65b0d8249f19a50245cd88ed1a2f78cff.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/162662 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
CVEID: CVE-2019-11478
DESCRIPTION: Jonathan Looney discovered that the TCP retransmission queue implementation in tcp_fragment in the Linux kernel could be fragmented when handling certain TCP Selective Acknowledgment (SACK) sequences. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit f070ef2ac66716357066b683fb0baf55f8191a2e.
CVSS Base score: 7.5
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/162664 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Affected Products and Versions
Affected Product(s) | Version(s) |
R7.5 | 87.52.x.x |
R8.4 | 88.4x.x.x |
R8.5 | 88.5x.x.x |
Remediation/Fixes
Fixes are provided for the releases noted below via ICS patch CVE_1Q2020_v1.0.iso. Systems which are below these levels should upgrade to at least the level shown below and then apply the ICS..
- 87.52.0.0 and above
- 88.40.62.0 and above
- 88.50.176.0 and above
Current recommended code levels can be found at https://www-01.ibm.com/support/docview.wss?uid=ssg1S1004456
NOTE
R9 ( 89.x.x.x) is not impacted.
Customers running releases below 88.40.62 on the DS8880 are advised to update to the recommended level of R88.50. and apply the update.
Customers running releases below 87.52.x.x on the DS8870 are advised to update to the recommended level of R87.52 and apply the update.
Customers should contact IBM service and request ICS CVE_1Q2020_v1.0.iso
Workarounds and Mitigations
None
Get Notified about Future Security Bulletins
References
Acknowledgement
Change History
25 Feb 2020: Initial Publication
25 Feb 2020: Correct errors in the summary
25 Feb 2020: Remove a dangling period and update product identifier
*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
Review the IBM security bulletin disclaimer and definitions regarding your responsibilities for assessing potential impact of security vulnerabilities to your environment.
Document Location
Worldwide
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Document Information
Modified date:
26 February 2020
UID
ibm13517185