SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-32845

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.

HIGH 7.8EPSS 0.25%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.25%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.25% probability · 16th percentile
CISA KEV
Not listed
Weakness
CWE-908, CWE-252
Affected
mobyproject/hyperkit
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.