CVE-2021-43816

Published Jan 5, 2022

Last updated 2 years ago

CVSS critical 9.1

Container Security

Overview

Description: containerd is an open source container runtime. On installations using SELinux, such as EL8 (CentOS, RHEL), Fedora, or SUSE MicroOS, with containerd since v1.5.0-beta.0 as the backing container runtime interface (CRI), an unprivileged pod scheduled to the node may bind mount, via hostPath volume, any privileged, regular file on disk for complete read/write access (sans delete). Such is achieved by placing the in-container location of the hostPath volume mount at either `/etc/hosts`, `/etc/hostname`, or `/etc/resolv.conf`. These locations are being relabeled indiscriminately to match the container process-label which effectively elevates permissions for savvy containers that would not normally be able to access privileged host files. This issue has been resolved in version 1.5.9. Users are advised to upgrade as soon as possible.
Source: security-advisories@github.com
NVD status: Modified

Risk scores

CVSS 3.1

Type: Primary
Base score: 9.1
Impact score: 6
Exploitability score: 2.3
Vector string: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Severity: CRITICAL

CVSS 2.0

Type: Primary
Base score: 6
Impact score: 6.4
Exploitability score: 6.8
Vector string: AV:N/AC:M/Au:S/C:P/I:P/A:P

Weaknesses

security-advisories@github.com: CWE-281
nvd@nist.gov: CWE-281

Hype score: Not currently trending

Configurations

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  {
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      {
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            "versionStartIncluding": "1.5.1",
            "vulnerable": true
          },
          {
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            "vulnerable": true
          },
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            "vulnerable": true
          },
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            "vulnerable": true
          },
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            "matchCriteriaId": "6D819271-9946-4A69-8EF7-AFF8AAA226CE",
            "vulnerable": true
          },
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            "vulnerable": true
          },
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            "vulnerable": true
          },
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            "vulnerable": true
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            "vulnerable": true
          },
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            "matchCriteriaId": "F43624CC-D1D3-4FF0-8D97-20E190A9A56E",
            "vulnerable": true
          }
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        "negate": false,
        "operator": "OR"
      }
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  },
  {
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      {
        "cpeMatch": [
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            "vulnerable": true
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      }
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  }
]

References

Sources include official advisories and independent security research.

Overview

Risk scores

CVSS 3.1

CVSS 2.0

Weaknesses

Social media

Configurations

Related CVEs

References