CVE-2017-7718

hw/display/cirrus_vga_rop.h in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (out-of-bounds read and QEMU process crash) via vectors related to copying VGA data via the cirrus_bitblt_rop_fwd_transp_ and cirrus_bitblt_rop_fwd_ functions.

Weakness

The product reads data past the end, or before the beginning, of the intended buffer.

Affected Software

Name	Vendor	Start Version	End Version
Qemu	Qemu	*	2.8.1.1 (including)
Qemu	Qemu	2.9.0-rc0 (including)	2.9.0-rc0 (including)
Red Hat Enterprise Linux 6	RedHat	qemu-kvm-2:0.12.1.2-2.503.el6_9.3	*
Red Hat Enterprise Linux 7	RedHat	qemu-kvm-10:1.5.3-126.el7_3.9	*
Red Hat Enterprise Linux OpenStack Platform 5.0 (Icehouse) for RHEL 6	RedHat	qemu-kvm-rhev-2:0.12.1.2-2.503.el6_9.3	*
Red Hat Enterprise Linux OpenStack Platform 5.0 (Icehouse) for RHEL 7	RedHat	qemu-kvm-rhev-10:2.6.0-28.el7_3.9	*
Red Hat Enterprise Linux OpenStack Platform 6.0 (Juno) for RHEL 7	RedHat	qemu-kvm-rhev-10:2.6.0-28.el7_3.9	*
Red Hat Enterprise Linux OpenStack Platform 7.0 (Kilo) for RHEL 7	RedHat	qemu-kvm-rhev-10:2.6.0-28.el7_3.9	*
Red Hat OpenStack Platform 10.0 (Newton)	RedHat	qemu-kvm-rhev-10:2.6.0-28.el7_3.9	*
Red Hat OpenStack Platform 8.0 (Liberty)	RedHat	qemu-kvm-rhev-10:2.6.0-28.el7_3.9	*
Red Hat OpenStack Platform 9.0 (Mitaka)	RedHat	qemu-kvm-rhev-10:2.6.0-28.el7_3.9	*
Red Hat Virtualization 4 for Red Hat Enterprise Linux 7	RedHat	qemu-kvm-rhev-10:2.6.0-28.el7_3.10	*
RHEV 3.X Hypervisor and Agents for RHEL-6	RedHat	qemu-kvm-rhev-2:0.12.1.2-2.503.el6_9.3	*
RHEV 3.X Hypervisor and Agents for RHEL-7	RedHat	qemu-kvm-rhev-10:2.6.0-28.el7_3.10	*
Qemu	Ubuntu	artful	*
Qemu	Ubuntu	bionic	*
Qemu	Ubuntu	cosmic	*
Qemu	Ubuntu	devel	*
Qemu	Ubuntu	disco	*
Qemu	Ubuntu	eoan	*
Qemu	Ubuntu	focal	*
Qemu	Ubuntu	groovy	*
Qemu	Ubuntu	hirsute	*
Qemu	Ubuntu	trusty	*
Qemu	Ubuntu	xenial	*
Qemu	Ubuntu	yakkety	*
Qemu	Ubuntu	zesty	*
Qemu-kvm	Ubuntu	precise	*
Qemu-kvm	Ubuntu	precise/esm	*

Potential Mitigations

Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
To reduce the likelihood of introducing an out-of-bounds read, ensure that you validate and ensure correct calculations for any length argument, buffer size calculation, or offset. Be especially careful of relying on a sentinel (i.e. special character such as NUL) in untrusted inputs.

https://cwe.mitre.org/data/definitions/540.html

NVD	https://nvd.nist.gov/vuln/detail/CVE-2017-7718
CWE	https://cwe.mitre.org/data/definitions/125.html

Out-of-bounds Read

Weakness

Affected Software

Potential Mitigations

References

CVE-2017-7718

Out-of-bounds Read

Weakness

Affected Software

Potential Mitigations

Related Attack Patterns

References