CVE-2017-1000405

Source
https://nvd.nist.gov/vuln/detail/CVE-2017-1000405
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2017-1000405.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2017-1000405
Related
Published
2017-11-30T22:29:00Z
Modified
2024-09-11T02:00:04Z
Severity
  • 7.0 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
Summary
[none]
Details

The Linux Kernel versions 2.6.38 through 4.14 have a problematic use of pmdmkdirty() in the touchpmd() function inside the THP implementation. touchpmd() can be reached by getuserpages(). In such case, the pmd will become dirty. This scenario breaks the new canfollowwritepmd()'s logic - pmd can become dirty without going through a COW cycle. This bug is not as severe as the original "Dirty cow" because an ext4 file (or any other regular file) cannot be mapped using THP. Nevertheless, it does allow us to overwrite read-only huge pages. For example, the zero huge page and sealed shmem files can be overwritten (since their mapping can be populated using THP). Note that after the first write page-fault to the zero page, it will be replaced with a new fresh (and zeroed) thp.

References

Affected packages

Debian:11 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.14.2-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:12 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.14.2-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:13 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.14.2-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}