Systems with microprocessors utilizing speculative execution may allow unauthorized disclosure of information to an attacker with local user access via a side-channel attack on the directional branch predictor, as demonstrated by a pattern history table (PHT), aka BranchScope. (CVE-2018-9056)
Impact
BIG-IP
There is no exposure on BIG-IP products by way of the data plane. All exposure is limited to the control plane (also known as the management plane).
In addition, on the control plane, the vulnerabilities are exploitable only by four authorized, authenticated account roles: Administrator, Resource Administrator, Manager, and iRules Manager. You must be authorized to access the system in one of these roles to even attempt to exploit the vulnerabilities.
This vulnerability requires an attacker who can provide and run binary code of their choosing on the BIG-IP platform.
These conditions severely restrict the exposure risk of BIG-IP products.
For single-tenancy products, such as a standalone BIG-IP appliance, the risk is limited to a local, authorized user using one of the vulnerabilities to read information from memory that they would not normally be able to access, exceeding their privileges. Effectively, the risk in a single-tenancy situation is that a user may be able to access kernel-space memory, instead of limited to their own user-space.
For multi-tenancy environments, such as cloud, Virtual Edition (VE), and Virtual Clustered Multiprocessing (vCMP), the same local risk applies as with single-tenancy environments, local kernel memory access. Additionally, the risk of attacks across guests exists, or attacks against the hypervisor/host. In cloud and VE environments, preventing this new attack falls on the hypervisor/host platform, outside the scope of F5’s ability to support or patch. Contact your cloud provider or hypervisor vendor to ensure their platforms or products are protected against BranchScope.
For vCMP environments, this risk exists only when vCMP guests are configured to use a single core. If the vCMP guests are configured to use two or more cores, the BranchScope vulnerability is eliminated.
F5 is working with their hardware component vendors to determine the scope of vulnerabilities across their various generations of hardware platforms. All of the information F5 currently has from their vendors is represented in this Security Advisory. F5 is working to obtain the remaining information from their vendors and will update the Security Advisory as F5 receives new information regarding their hardware platforms.
F5 is also testing the fixes produced by the Linux community, and is conducting an extensive test campaign to characterize the impact of the fixes on system performance and stability to ensure a good experience for customers. F5 does not want to rush the process and release fixes without a full understanding of potential issues. Given the limited exposure (as detailed above), the complexity of the fixes, and the potential issues seen, a detailed approach is warranted and rushing a fix may result in an impact to system stability or unacceptable performance costs. This article will be updated with details of fixes as they become available.
To determine which vulnerabilities affect each platform and the processor type each platform uses, refer to the following table.
Note: In the following table, only one entry is shown for platform models that may have several variants. For example, BIG-IP 11000, BIG-IP 11050, BIG-IP 11050F, and BIG-IP 11050N are all vulnerable and included in the table asBIG-IP 110x0. Some platforms may have multiple vendor processors, such as the iSeries platforms, which have one or more Intel core processors and may have a vulnerable ARM processor in one or more subsystems. F5 does not believe that ARM processors in these subsystems are accessible to attackers, unless some other code-execution vulnerability is present, but the information is provided out of an abundance of caution.
Model | Processor Type | Vulnerable to CVE-2018-9056 BranchScope |
---|---|---|
VIPRION B21x0 | Intel | Y |
VIPRION B2250 | Intel | Y |
VIPRION B4100 | AMD | Y** |
VIPRION B4200 | AMD | Y** |
VIPRION B43x0 | Intel | Y |
VIPRION B44x0 | Intel | Y |
BIG-IP 800 | Intel | N |
BIG-IP 1600 | Intel | N |
BIG-IP 3600 | Intel | N |
BIG-IP 3900 | Intel | N |
BIG-IP 2xx0 | Intel | Y |
BIG-IP 4xx0 | Intel | Y |
BIG-IP 5xx0 | Intel | Y |
BIG-IP 7xx0 | Intel | Y |
BIG-IP 10xx0 | Intel | Y |
BIG-IP 12xx0 | Intel | Y |
BIG-IP i2x00 | Intel, ARM | Y |
BIG-IP i4x00 | Intel, ARM | Y |
BIG-IP i5x00 | Intel, ARM | Y |
BIG-IP i7x00 | Intel, ARM | Y |
BIG-IP i10x00 | Intel, ARM | Y |
BIG-IP 6400 | AMD | Y** |
BIG-IP 6900 | AMD | Y** |
BIG-IP 89x0 | AMD | Y** |
BIG-IP 110x0 | AMD | Y** |
** Intel and AMD have not responded to requests for information relating to the specific processors used in these platforms. Based on their public statements and in the interests of security, F5 will proceed as if these platforms are vulnerable.
Note: Platform models that have reached End of Technical Support (EoTS) will not be evaluated. For more information, refer to K4309: F5 platform lifecycle support policy.
BIG-IQ, F5 iWorkflow, and Enterprise Manager
Systems with microprocessors that use speculative execution and indirect branch prediction may allow unauthorized disclosure of information to an attacker with local user access by way of a side-channel analysis.
To determine which vulnerabilities affect each platform and the processor type each platform uses, refer to the following table.
Model | Processor Type | Vulnerable to CVE-2018-9056 BranchScope |
---|---|---|
BIG-IQ 7000 | Intel | Y |
Enterprise Manager 4000 | Intel | N |
Note: Platform models that have reached End of Technical Support (EoTS) will not be evaluated. For more information, refer to K4309: F5 platform lifecycle support policy.
LineRate
Systems with microprocessors that use speculative execution and indirect branch prediction may allow unauthorized disclosure of information to an attacker with local user access by way of a side-channel analysis.
For products with None in theVersions known to be vulnerable column in the following table, there is no impact.