Description
The Linux Kernel versions 2.6.38 through 4.14 have a problematic use of pmd_mkdirty() in the touch_pmd() function inside the THP implementation. touch_pmd() can be reached by get_user_pages(). In such case, the pmd will become dirty. This scenario breaks the new can_follow_write_pmd()'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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 4.14.2-1 | — |
| Debian 13 | linux | 4.14.2-1 | — |
| Debian 12 | linux | 4.14.2-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux-raspi-realtime | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +2 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +3 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-hwe +1 | No fix yet | — |
| Ubuntu 16.04 LTS | linux | 4.4.0-103.126 | USN-3509-1 |
| Ubuntu 16.04 LTS | linux-aws | 4.4.0-1043.52 | USN-3509-1 |
| Ubuntu 16.04 LTS | linux-azure | 4.11.0-1016.16 | USN-3511-1 |
| Ubuntu 16.04 LTS | linux-gcp | 4.13.0-1002.5 | USN-3507-2 |
| Ubuntu 16.04 LTS | linux-hwe | 4.13.0-32.35~16.04.1 | USN-3508-2 |
| Ubuntu 16.04 LTS | linux-kvm | 4.4.0-1012.17 | USN-3509-1 |
| Ubuntu 16.04 LTS | linux-oem | 4.13.0-1010.11 | — |
| Ubuntu 16.04 LTS | linux-raspi2 | 4.4.0-1079.87 | USN-3509-1 |
| Ubuntu 16.04 LTS | linux-snapdragon | 4.4.0-1081.86 | USN-3509-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 14.04 LTS | linux | 3.13.0-137.186 | USN-3510-1 |
| Ubuntu 14.04 LTS | linux-aws | 4.4.0-1005.5 | USN-3509-2 |
| Ubuntu 14.04 LTS | linux-lts-xenial | 4.4.0-103.126~14.04.1 | USN-3509-2 |
| Ubuntu Pro FIPS-updates 16.04 LTS | linux-fips | 4.4.0-1005.5 | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | perf +15 | 4.11.0-44.4.1.el7a | RHSA-2018:0180 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP3 | kernel-docs | 4.4.92-6.30.2 | SUSE-SU-2017:3225-1 |
| SLES 12 SP3 | kernel-syms +3 | 4.4.92-6.30.1 | SUSE-SU-2017:3225-1 |
| SLES 12 SP2 | kernel-docs | 4.4.90-92.50.3 | SUSE-SU-2017:3226-1 |
| SLES 12 SP2 | kernel-syms +3 | 4.4.90-92.50.1 | SUSE-SU-2017:3226-1 |
| SLES 12 SP1 | kernel-xen +3 | 3.12.74-60.64.66.1 | SUSE-SU-2017:3210-1 |
| SLES 12 SP1 | kgraft-patch-SLE12-SP1_Update_23 | 1-2.1 | SUSE-SU-2017:3210-1 |
| SLES 12 | kernel-ec2 +4 | 3.12.61-52.106.1 | SUSE-SU-2017:3249-1, SUSE-SU-2017:3210-1 |
| SLES 12 | kgraft-patch-SLE12_Update_29 | 1-5.1 | SUSE-SU-2017:3249-1 |
Show 11 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP3 | kernel-syms +2 | 4.4.92-6.30.1 | SUSE-SU-2017:3225-1 |
| SLES for SAP 12 SP2 | kernel-syms +2 | 4.4.90-92.50.1 | SUSE-SU-2017:3226-1 |
| SLES for SAP 12 SP1 | kernel-xen +3 | 3.12.74-60.64.66.1 | SUSE-SU-2017:3210-1 |
| SLES for SAP 12 SP1 | kgraft-patch-SLE12-SP1_Update_23 | 1-2.1 | SUSE-SU-2017:3210-1 |
| SLE Real Time 12 SP2 | kernel-rt +3 | 4.4.104-24.1 | SUSE-SU-2018:0213-1 |
| SLE Live Patching 15 SP1 | kernel-livepatch-SLE15-SP1_Update_7 | 8-2.2 | SUSE-SU-2020:3400-1 |
| SLE Live Patching 15 | kernel-livepatch-SLE15_Update_16 | 8-2.2 | SUSE-SU-2020:3449-1 |
| SLE Live Patching 12 SP5 | kgraft-patch-SLE12-SP5_Update_0 | 8-21.2 | SUSE-SU-2020:3400-1 |
| SLE Live Patching 12 SP5 | kgraft-patch-SLE12-SP5_Update_1 | 8-2.2 | SUSE-SU-2020:3400-1 |
| SLE Live Patching 12 SP4 | kgraft-patch-SLE12-SP4_Update_10 | 8-2.2 | SUSE-SU-2020:3449-1 |
| SLE Live Patching 12 SP3 | kgraft-patch-SLE12-SP3_Update_1 | 4-2.1 | SUSE-SU-2017:3319-1 |
| SLE Live Patching 12 SP3 | kgraft-patch-SLE12-SP3_Update_2 +1 | 3-2.1 | SUSE-SU-2017:3324-1, SUSE-SU-2017:3314-1 |
| SLE Live Patching 12 SP3 | kgraft-patch-SLE12-SP3_Update_4 | 2-2.1 | SUSE-SU-2017:3317-1 |
| SLE Live Patching 12 SP3 | kgraft-patch-SLE12-SP3_Update_5 | 1-6.1 | SUSE-SU-2017:3225-1 |
| SLE Live Patching 12 | kgraft-patch-SLE12-SP2_Update_11 +1 | 5-2.1 | SUSE-SU-2017:3295-1, SUSE-SU-2017:3284-1 |
| SLE Live Patching 12 | kgraft-patch-SLE12-SP2_Update_13 | 4-2.1 | SUSE-SU-2017:3297-1 |
| SLE Live Patching 12 | kgraft-patch-SLE12-SP2_Update_14 | 2-2.1 | SUSE-SU-2017:3285-1 |
| SLE Live Patching 12 | kgraft-patch-SLE12-SP2_Update_15 | 1-4.1 | SUSE-SU-2017:3226-1 |
| SLE Live Patching 12 | kgraft-patch-SLE12-SP2_Update_7 +1 | 7-2.1 | SUSE-SU-2017:3310-1, SUSE-SU-2017:3286-1 |
| SLE Live Patching 12 | kgraft-patch-SLE12-SP2_Update_9 +1 | 6-2.1 | SUSE-SU-2017:3300-1, SUSE-SU-2017:3296-1 |
| SUSE OpenStack Cloud 6 | kernel-xen +3 | 3.12.74-60.64.66.1 | SUSE-SU-2017:3210-1 |
| SUSE OpenStack Cloud 6 | kgraft-patch-SLE12-SP1_Update_23 | 1-2.1 | SUSE-SU-2017:3210-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2 | perf +8 | 4.9.81-44.57.amzn2 | ALAS2-2018-956 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | kernel-uek +5 | 4.1.12-103.10.1.el7uek | ELSA-2017-3651 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.
Exploit-DB 2
- Linux Kernel - 'The Huge Dirty Cow' Overwriting The Huge Zero Page (2) EDB-44305 · dos · Dec 11, 2017
- Linux Kernel - 'The Huge Dirty Cow' Overwriting The Huge Zero Page (1) EDB-43199 · dos · Nov 30, 2017
GitHub 1 repository
-
bindecy/HugeDirtyCowPOC ★ 200 · Nov 29, 2017
A POC for the Huge Dirty Cow vulnerability (CVE-2017-1000405)
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 29
- RHSA-2018:0180 Red Hat Security Advisory: kernel-alt security and bug fix update Red Hat Security Advisories (RHSA) · Jun 29, 2026
- WID-SEC-2026-1693 Linux Kernel: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · May 27, 2026
- USN-3510-1 linux vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-3509-1 linux, linux-aws, linux-kvm, linux-raspi2, linux-snapdragon vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-3508-2 linux-hwe vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- USN-3509-2 linux-lts-xenial, linux-aws vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- USN-3511-1 linux-azure vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- USN-3507-2 linux-gcp vulnerabilities Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2017:3297-1 Security update for the Linux Kernel (Live Patch 13 for SLE 12 SP2) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3226-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2018:0213-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3284-1 Security update for the Linux Kernel (Live Patch 11 for SLE 12 SP2) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3319-1 Security update for the Linux Kernel (Live Patch 1 for SLE 12 SP3) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3210-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3285-1 Security update for the Linux Kernel (Live Patch 14 for SLE 12 SP2) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:3449-1 Security update for the Linux Kernel (Live Patch 16 for SLE 15) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3286-1 Security update for the Linux Kernel (Live Patch 8 for SLE 12 SP2) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3314-1 Security update for the Linux Kernel (Live Patch 3 for SLE 12 SP3) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3249-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3324-1 Security update for the Linux Kernel (Live Patch 2 for SLE 12 SP3) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3225-1 Security update for the Linux Kernel SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2020:3400-1 Security update for the Linux Kernel (Live Patch 7 for SLE 15 SP1) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3317-1 Security update for the Linux Kernel (Live Patch 4 for SLE 12 SP3) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3296-1 Security update for the Linux Kernel (Live Patch 9 for SLE 12 SP2) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3300-1 Security update for the Linux Kernel (Live Patch 10 for SLE 12 SP2) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3295-1 Security update for the Linux Kernel (Live Patch 12 for SLE 12 SP2) SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2017:3310-1 Security update for the Linux Kernel (Live Patch 7 for SLE 12 SP2) SUSE / openSUSE Security Updates · May 2, 2025
- ALAS2-2018-956 Important: kernel security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Feb 21, 2018
- ELSA-2017-3651 Important: Unbreakable Enterprise kernel security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Dec 7, 2017
References
- 102032 vdb-entry
- RHSA-2018:0180 vendor-advisory
- https://medium.com/bindecy/huge-dirty-cow-cve-2017-1000405-110eca132de0
- https://source.android.com/security/bulletin/pixel/2018-02-01
- 1040020 vdb-entry
- 43199 exploit