CVE-2021-32845

Moby HyperKit uninitialized memory use vtrnd pci_vtrnd_notify

Description

HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, the implementation of `qnotify` at `pci_vtrnd_notify` fails to check the return value of `vq_getchain`. This leads to `struct iovec iov;` being uninitialized and used to read memory in `len = (int) read(sc->vrsc_fd, iov.iov_base, iov.iov_len);` when an attacker is able to make `vq_getchain` fail. This issue may lead to a guest crashing the host causing a denial of service and, under certain circumstance, memory corruption. This issue is fixed in commit 41272a980197917df8e58ff90642d14dec8fe948.

Categories

7.7
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.03%
Third-Party Advisory github.com
Affected: moby hyperkit
Published at:
Updated at:

References

Link Tags
https://securitylab.github.com/advisories/GHSL-2021-054_057-moby-hyperkit/ third party advisory
https://github.com/moby/hyperkit/pull/313 patch
https://github.com/moby/hyperkit/commit/41272a980197917df8e58ff90642d14dec8fe948 patch

Frequently Asked Questions

What is the severity of CVE-2021-32845?
CVE-2021-32845 has been scored as a high severity vulnerability.
How to fix CVE-2021-32845?
To fix CVE-2021-32845, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-32845 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-32845 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-32845?
CVE-2021-32845 affects moby hyperkit.
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