SB2022062124 - Ubuntu update for qemu

Description

This security bulletin contains information about 7 vulnerabilities.

1) Heap-based buffer overflow (CVE-ID: CVE-2021-3507)

CWE-ID: CWE-122 - Heap-based Buffer Overflow

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary error in the fdctrl_transfer_handler() function in hw/block/fdc.c while processing DMA read data transfers from the floppy drive to the guest system. A remote privileged user on the guest OS can trigger a heap-based buffer overflow and crash the QEMU process on the host OS.

2) Use-after-free (CVE-ID: CVE-2021-3929)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote user to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in the NVM Express Controller emulation in QEMU within the dma_buf_write() and dma_buf_read() function in hw/nvme/ctrl.c:nvme_tx(). A remote privileged user on the guest OS can trigger a use-after-free error and execute arbitrary code on the QEMU host.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

3) Integer overflow (CVE-ID: CVE-2021-4206)

CWE-ID: CWE-190 - Integer overflow

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local user to escalate privileges on the target system.

The vulnerability exists due to integer overflow in the cursor_alloc() function in the QXL display device emulation in QEMU. A privileged user can crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.

4) Race condition (CVE-ID: CVE-2021-4207)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a race condition in the QXL display device emulation in QEMU. A privileged user can exploit the race and gain unauthorized access to sensitive information and escalate privileges on the system.

5) Incorrect default permissions (CVE-ID: CVE-2022-0358)

CWE-ID: CWE-276 - Incorrect Default Permissions

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to incorrect QEMU virtio-fs shared file system daemon (virtiofsd) implementation. An attacker on the guest OS can create files in the directories shared by virtio-fs with unintended group ownership in a scenario where a directory is SGID to a certain group and is writable by a user who is not a member of the group. This can lead to privilege escalation within the guest OS.

The vulnerability exists due to incomplete fox for #VU13631 (CVE-2018-13405).

6) Use-after-free (CVE-ID: CVE-2022-26353)

CWE-ID: CWE-416 - Use After Free

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local user to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in the virtio-net device of QEMU. A privileged user can exploit this issue to crash QEMU or potentially execute arbitrary code with elevated privileges.

7) Improper Resource Shutdown or Release (CVE-ID: CVE-2022-26354)

CWE-ID: CWE-404 - Improper Resource Shutdown or Release

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local user to gain access to sensitive information.

The vulnerability exists in the vhost-vsock device of QEMU. A local user can trigger the error and gain access to sensitive information.

Remediation

Install update from vendor's website.

References

• https://ubuntu.com/security/notices/USN-5489-1