Debian update for docker.io

1) Insufficiently protected credentials

EUVDB-ID: #VU48721

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-15157

CWE-ID: CWE-522 - Insufficiently Protected Credentials

Exploit availability: No

Description

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

If a container image manifest in the OCI Image format or Docker Image V2 Schema 2 format includes a URL for the location of a specific image layer (otherwise known as a “foreign layer”), the default containerd resolver will follow that URL to attempt to download it. In v1.2.x the default containerd resolver will provide its authentication credentials if the server where the URL is located presents an HTTP 401 status code along with registry-specific HTTP headers.

If an attacker publishes a public image with a manifest that directs one of the layers to be fetched from a web server they control and they trick a user or system into pulling the image, they can obtain the credentials used for pulling that image. In some cases, this may be the user's username and password for the registry. In other cases, this may be the credentials attached to the cloud virtual instance which can grant access to other cloud resources in the account.

The default containerd resolver is used by the cri-containerd plugin (which can be used by Kubernetes), the ctr development tool, and other client programs that have explicitly linked against it.

Mitigation

Update docker.io package to version 18.09.1+dfsg1-7.1+deb10u3.

Vulnerable software versions

docker.io (Debian package): 18.09.1+dfsg1-7.1+deb10u1 - 18.09.1+dfsg1-7~deb10u1

External links

http://www.debian.org/security/2021/dsa-4865

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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

2) Improper access control

EUVDB-ID: #VU48795

Risk: Medium

CVSSv3.1: 6.9 [CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:P/RL:O/RC:C]

CVE-ID: CVE-2020-15257

CWE-ID: CWE-284 - Improper Access Control

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions. Access controls for the shim’s API socket verified that the connecting process had an effective UID of 0, but did not otherwise restrict access to the abstract Unix domain socket. This would allow malicious containers running in the same network namespace as the shim, with an effective UID of 0 but otherwise reduced privileges, to cause new processes to be run with elevated privileges.

Mitigation

Update docker.io package to version 18.09.1+dfsg1-7.1+deb10u3.

Vulnerable software versions

docker.io (Debian package): 18.09.1+dfsg1-7.1+deb10u1 - 18.09.1+dfsg1-7~deb10u1

External links

http://www.debian.org/security/2021/dsa-4865

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.

3) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU50273

Risk: Medium

CVSSv3.1: 7 [CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-21284

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a remote attacker to escalate privileges on the system.

The vulnerability exists due to application does not properly impose security restrictions when using the --userns-remap option. A remote authenticated attacker on the local network can send a specially crafted request and gain elevated privileges as root on the system.

Mitigation

Update docker.io package to version 18.09.1+dfsg1-7.1+deb10u3.

Vulnerable software versions

docker.io (Debian package): 18.09.1+dfsg1-7.1+deb10u1 - 18.09.1+dfsg1-7~deb10u1

External links

http://www.debian.org/security/2021/dsa-4865

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

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

4) Resource exhaustion

EUVDB-ID: #VU50274

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-21285

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No

Description

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

The vulnerability exists due to application does not properly control consumption of internal resources. A remote attacker can trick a victim to pull a specially crafted Docker image, trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation

Update docker.io package to version 18.09.1+dfsg1-7.1+deb10u3.

Vulnerable software versions

docker.io (Debian package): 18.09.1+dfsg1-7.1+deb10u1 - 18.09.1+dfsg1-7~deb10u1

External links

http://www.debian.org/security/2021/dsa-4865

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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