---
title: "CVE-2016-1575\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2016-1575?format=md
keywords: index, follow
---

# CVE-2016-1575

Publication date 22 February 2016

Last updated 4 July 2026

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**7.8 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2016-1575?format=md#impact-score)

Toggle side navigation

## Description

The overlayfs implementation in the Linux kernel through 4.5.2 does not
properly maintain POSIX ACL xattr data, which allows local users to gain
privileges by leveraging a group-writable setgid directory.

### From the Ubuntu Security Team

halfdog discovered that OverlayFS in the Linux kernel incorrectly
propagated security sensitive extended attributes, such as POSIX ACLs. A
local unprivileged attacker could use this to gain privileges.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2016-1575?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| linux | 17.04 zesty | Not affected |
| 16.10 yakkety | Not affected |
| 16.04 LTS xenial | Not affected |
| 15.10 wily | Fixed 4.2.0-30.35 |
| 15.04 vivid | Fixed 3.19.0-51.57 |
| 14.04 LTS trusty | Fixed 3.13.0-79.123 |
| 12.04 LTS precise | Ignored end of life |
| linux-armadaxp | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |
| linux-aws | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not affected |
| 12.04 LTS precise | Not in release |
| linux-flo | 17.04 zesty | Not in release |
| 16.10 yakkety | Ignored end of life |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Ignored end of life |
| 15.04 vivid | Ignored end of life |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-gke | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-goldfish | 17.04 zesty | Ignored end of life |
| 16.10 yakkety | Ignored end of life |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Ignored end of life |
| 15.04 vivid | Ignored end of life |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-grouper | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-hwe | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-hwe-edge | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-linaro-omap | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |
| linux-linaro-shared | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |
| linux-linaro-vexpress | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |
| linux-lts-quantal | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |
| linux-lts-raring | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |
| linux-lts-saucy | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |
| linux-lts-trusty | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Fixed 3.13.0-79.123~precise1 |
| linux-lts-utopic | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Fixed 3.16.0-62.82~14.04.1 |
| 12.04 LTS precise | Not in release |
| linux-lts-vivid | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Fixed 3.19.0-51.57~14.04.1 |
| 12.04 LTS precise | Not in release |
| linux-lts-wily | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Fixed 4.2.0-30.35~14.04.1 |
| 12.04 LTS precise | Not in release |
| linux-lts-xenial | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not affected |
| 12.04 LTS precise | Not in release |
| linux-maguro | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-mako | 17.04 zesty | Not in release |
| 16.10 yakkety | Ignored end of life |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Ignored end of life |
| 15.04 vivid | Ignored end of life |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-manta | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Ignored end of life |
| 15.04 vivid | Ignored end of life |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-qcm-msm | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |
| linux-raspi2 | 17.04 zesty | Not affected |
| 16.10 yakkety | Not affected |
| 16.04 LTS xenial | Not affected |
| 15.10 wily | Fixed 4.2.0-1025.32 |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-snapdragon | 17.04 zesty | Not affected |
| 16.10 yakkety | Not affected |
| 16.04 LTS xenial | Not affected |
| 15.10 wily | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Not in release |
| linux-ti-omap4 | 17.04 zesty | Not in release |
| 16.10 yakkety | Not in release |
| 16.04 LTS xenial | Not in release |
| 15.10 wily | Not in release |
| 15.04 vivid | Not in release |
| 14.04 LTS trusty | Not in release |
| 12.04 LTS precise | Ignored end of life |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2016-1575?format=md#patch-details)

## Notes

---

### [jdstrand](https://launchpad.net/~jdstrand)

android kernels (flo, goldfish, grouper, maguro, mako and manta) are
not supported on the Ubuntu Touch 14.10 and earlier preview kernels
linux-lts-saucy no longer receives official support
linux-lts-quantal no longer receives official support

---

### [sbeattie](https://launchpad.net/~sbeattie)

precise does not allow unprivileged user namespaces,
which is what lets an unprivileged user exploit this vulnerability;
however, the issue of copying up setuid attributes still exists in
the overlayfs codebase here, but it is a much lower priority to fix
(needs root/CAP\_SYS\_ADMIN to exploit).

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| linux | * Introduced by   [e9be9d5](https://git.kernel.org/linus/e9be9d5e76e34872f0c37d72e25bc27fe9e2c54c|local-overlayfs-backport),   fixed by   [1175b6b](https://git.kernel.org/linus/1175b6b8d96331676f1d436b089b965807f23b4a) * Introduced by   [e9be9d5](https://git.kernel.org/linus/e9be9d5e76e34872f0c37d72e25bc27fe9e2c54c|local-overlayfs-backport),   fixed by   [local-2](https://git.kernel.org/linus/local-2016-1575-2) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.8 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Local |
  | Attack complexity | Low |
  | Privileges required | Low |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | High |
  | Availability impact | High |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.8 · High |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-1575)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-1575)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-1575)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2016-1575)

### Related Ubuntu Security Notices (USN)

+ [USN-2909-1](https://usn.ubuntu.com/USN-2909-1)
+ Linux kernel (Utopic HWE) vulnerabilities
+ 22 February 2016

+ [USN-2908-2](https://usn.ubuntu.com/USN-2908-2)
+ Linux kernel (Wily HWE) vulnerabilities
+ 22 February 2016

+ [USN-2910-1](https://usn.ubuntu.com/USN-2910-1)
+ Linux kernel (Vivid HWE) vulnerabilities
+ 22 February 2016

+ [USN-2908-3](https://usn.ubuntu.com/USN-2908-3)
+ Linux kernel (Raspberry Pi 2) vulnerabilities
+ 22 February 2016

+ [USN-2908-1](https://usn.ubuntu.com/USN-2908-1)
+ Linux kernel vulnerabilities
+ 22 February 2016

+ [USN-2907-1](https://usn.ubuntu.com/USN-2907-1)
+ Linux kernel vulnerabilities
+ 22 February 2016

+ [USN-2907-2](https://usn.ubuntu.com/USN-2907-2)
+ Linux kernel (Trusty HWE) vulnerabilities
+ 22 February 2016

### Other references

* <http://www.halfdog.net/Security/2016/UserNamespaceOverlayfsXattrSetgidPrivilegeEscalation/>
* <https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/trusty/commit/?id=4dc7ebf4284cdc90e8f3cd617ed247aade2ca39f>
* <https://www.cve.org/CVERecord?id=CVE-2016-1575>
