Ubuntu update for linux-kvm

1) Race condition

EUVDB-ID: #VU54292

Risk: Medium

CVSSv4.0: 7.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2021-3609

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

Exploit availability: No

Description

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

The vulnerability exists due to a race condition in the CAN BCM networking protocol (net/can/bcm.c) in the Linux kernel ranging from version 2.6.25 to mainline 5.13-rc6. A local user can exploit the race and gain unauthorized access to sensitive information and escalate privileges on the system.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.

2) Out-of-bounds write

EUVDB-ID: #VU87989

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-33200

CWE-ID: CWE-787 - Out-of-bounds write

Exploit availability: No

Description

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

The vulnerability exists due to a boundary error in kernel/bpf/verifier.c. A local user can trigger an out-of-bounds write and escalate privileges on the system.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Input validation error

EUVDB-ID: #VU53154

Risk: Low

CVSSv4.0: 2.3 [CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-24586

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

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

The vulnerability exists in the 802.11 standard due to the affected device does not clear its cache/memory to remove fragments of an incomplete MSDU/MMPDU from previous session after reconnection/reassociation. A remote attacker on the local network can perform a fragment cache attack and perform a denial of service (DoS) attack.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

4) Information disclosure

EUVDB-ID: #VU53096

Risk: Low

CVSSv4.0: 4.9 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-24587

CWE-ID: N/A

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output by the application in Windows Wireless Networking. A remote attacker on the local network can gain unauthorized access to sensitive information on the system.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

5) Spoofing attack

EUVDB-ID: #VU53098

Risk: Low

CVSSv4.0: 1.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-24588

CWE-ID: CWE-451 - User Interface (UI) Misrepresentation of Critical Information (Clickjacking, spoofing)

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform spoofing attack.

The vulnerability exists due to incorrect processing of user-supplied data in Windows Wireless Networking. A remote attacker on the local network can spoof page content.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

6) Input validation error

EUVDB-ID: #VU53174

Risk: Low

CVSSv4.0: 4.9 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-26139

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to forwarding EAPOL frames even though the sender is not yet authenticated. A remote attacker on the local network can cause a denial of service (DoS) condition on the target system.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

7) Input validation error

EUVDB-ID: #VU53176

Risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:A/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-26141

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to the Wi-Fi implementation does not verify the Message Integrity Check (authenticity) of fragmented TKIP frames. A remote attacker on the local network can inject and possibly decrypt packets in WPA or WPA2 networks that support the TKIP data-confidentiality protocol.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

8) Input validation error

EUVDB-ID: #VU53155

Risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-26145

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to the WEP, WPA, WPA2, and WPA3 implementations accept second (or subsequent) broadcast fragments even when sent in plaintext and process them as full unfragmented frames. A remote attacker on the local network can inject arbitrary network packets independent of the network configuration.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

9) Input validation error

EUVDB-ID: #VU53172

Risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-26147

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to the WEP, WPA, WPA2, and WPA3 implementations reassemble fragments even though some of them were sent in plaintext. A remote attacker on the local network can inject packets and/or exfiltrate selected fragments

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

10) Race condition

EUVDB-ID: #VU53006

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-23133

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

Exploit availability: No

Description

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

The vulnerability exists due to a race condition in Linux kernel SCTP sockets (net/sctp/socket.c). If sctp_destroy_sock is called without sock_net(sk)->sctp.addr_wq_lock then an element is removed from the auto_asconf_splist list without any proper locking. This can be exploited by a local user with network service privileges to escalate to root or from the context of an unprivileged user directly if a BPF_CGROUP_INET_SOCK_CREATE is attached which denies creation of some SCTP socket.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

11) Use-after-free

EUVDB-ID: #VU63657

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-23134

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

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

The vulnerability exists due to a use-after-free error in nfc sockets in the Linux Kernel. A local user with the CAP_NET_RAW capability can trigger use-after-free and escalate privileges on the system.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

12) Information disclosure

EUVDB-ID: #VU67181

Risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-31829

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

Exploit availability: No

Description

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

The vulnerability exists due to excessive data output in the Linux kernel's eBPF verification code. A local user can insert eBPF instructions, use the eBPF verifier to abuse a spectre-like flaw and infer all system memory.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

13) Race condition

EUVDB-ID: #VU55257

Risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-32399

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

Exploit availability: No

Description

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

The vulnerability exists due to a race condition for removal of the HCI controller within net/bluetooth/hci_request.c in the Linux kernel. A local user can exploit the race and gain unauthorized access to sensitive information and escalate privileges on the system.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

14) Use-after-free

EUVDB-ID: #VU54454

Risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-33034

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

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

The vulnerability exists due to a use-after-free error in net/bluetooth/hci_event.c when destroying an hci_chan. A local user can escalate privileges on the system.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

15) Out-of-bounds read

EUVDB-ID: #VU53007

Risk: Low

CVSSv4.0: 4.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-3506

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

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

The vulnerability exists due to a boundary condition in fs/f2fs/node.c in the f2fs module in the Linux kernel. A local user can trigger out-of-bounds read error and read internal kernel information or crash the system.

Mitigation

Update the affected package linux-kvm to the latest version.

Vulnerable software versions

Ubuntu: 20.04

linux-image-kvm (Ubuntu package): before 5.4.0.1041.39

linux-image-5.4.0-1041-kvm (Ubuntu package): before 5.4.0-1041.42

CPE2.3

External links

https://ubuntu.com/security/notices/USN-5000-2

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

Risk	Medium
Patch available	YES
Number of vulnerabilities	15
CVE-ID	CVE-2021-3609 CVE-2021-33200 CVE-2020-24586 CVE-2020-24587 CVE-2020-24588 CVE-2020-26139 CVE-2020-26141 CVE-2020-26145 CVE-2020-26147 CVE-2021-23133 CVE-2021-23134 CVE-2021-31829 CVE-2021-32399 CVE-2021-33034 CVE-2021-3506
CWE-ID	CWE-362 CWE-787 CWE-20 CWE-451 CWE-416 CWE-200 CWE-125
Exploitation vector	Local network
Public exploit	Public exploit code for vulnerability #1 is available.
Vulnerable software	Ubuntu Operating systems & Components / Operating system linux-image-kvm (Ubuntu package) Operating systems & Components / Operating system package or component linux-image-5.4.0-1041-kvm (Ubuntu package) Operating systems & Components / Operating system package or component
Vendor	Canonical Ltd.