On January 27, 2020, intel released a security update that disclosed two security vulnerabilities of Intel processors that could lead to information disclosure. CVE numbers are CVE-2020-0548 and CVE-2020-0549. Intel will be providing fixes in future microcode updates. The vulnerability details are as follows:
CVE-2020-0549：L1D Eviction Sampling
On some processors under certain microarchitectural conditions, data from the most recently evicted modified L1 data cache (L1D) line may be propagated into an unused (invalid) L1D fill buffer. On processors affected by Microarchitectural Data Samping (MDS) or Transactional Asynchronous Abort (TAA), data from an L1D fill buffer may be inferred using one of these data sampling side channel methods. By combining these two behaviors together, it may be possible for a malicious actor to infer data values from modified cache lines that were previously evicted from the L1 data cache. This is called L1D eviction sampling.
CVE-2020-0548
Cleanup errors in some data cache evictions for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access. This vulnerability has been assigned CVE-2020-0549 with a CVSS of 2.8.
KAYTUS started the relevant investigation work in the first time. KAYTUS will be working closely with Intel to provide security updates. KAYTUS PSIRT will update the security notice at any time. Please keep an eye on the security bulletin for this incident.
The affected products and corresponding update versions are shown in the table below.
| CVE | V3.1 Vector(Base) | Base Score | V3.1 Vector(Temporal Score) | Temporal Score |
| CVE-2020-0549 | AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N | 5.5 | E:U/RL:O/RC:C | 4.8 |
| CVE-2020-0548 | AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N | 5.5 | E:U/RL:O/RC:C | 4.8 |
| Product | BIOS Update version |
| SN5161M5 | SN5161M5_BIOS_4.1.04_Standard_20200228 |
| TS860M5 | TS860M5_BIOS_4.1.11_Standard_20200303 |
| NS5162M5 | NS5162M5_BIOS_4.1.10_Standard_20200429 |
| NF5468M5 | NF5468M5_BIOS_4.1.14_Standard_20200327 |
| NF5288M5 | NF5288M5_BIOS_4.1.08_Standard_20200503 |
| NF8480M5 | NF8480M5_BIOS_4.1.13_Standard_20200428 |
| NX5460M5 | NX5460M5_BIOS_4.1.06_Standard_20200504 |
| NF5180M5 | NF5180M5_BIOS_4.1.10_Standard_20200522 |
| NS5488M5 NS5484M5 NS5482M5 |
Sentosa_BIOS_4.1.10_standard_20200502 |
| NF8380M5 | NF8380M5_BIOS_4.1.5_Standard_20200506 |
| NF8260M5 | NF8260M5_BIOS_4.1.13_Standard_20200422 |
| NF5266M5 | NF5266M5_BIOS_3.1.5_Standard_20200512 |
| NF5280M5 | NF5280M5_BIOS_4.1.16_Standard_20200623 |
KAYTUS provides method to update CPU Microcode of its various products as mentioned in the table above.Download your product’s corresponding BIOS image and perform the BIOS upgrade.
Please visit the Support Center site for updates on the applicable products.
20200713-V1.2-Updated The Fix Version
20200609-V1.1-Updated The Fix Version
20200522-V1.0-Initl Release
For issues about implementing the recommendations of this Security Bulletin, contact normal KAYTUS Services Support channel. For other issues about the content of this Security Bulletin, send e-mail to sec@kaytus.com.
To report a potential security vulnerability for KAYTUS product: Reporting a Security Vulnerability
KAYTUS shall not be liable for technical or editorial errors or omissions contained herein. The information provided is provided "as is" without warranty of any kind. To the extent permitted by law, KAYTUS disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose, title and non-infringement. In no event shall KAYTUS or any of its directly or indirectly controlled subsidiaries or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages. Your use of the document, by whatsoever means, will be totally at your own risk. KAYTUS is entitled to amend or update this document from time to time.