CVE-2019-15793

In shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, several locations which shift ids translate user/group ids before performing operations in the lower filesystem were translating them into init_user_ns, whereas they should have been translated into the s_user_ns for the lower filesystem. This resulted in using ids other than the intended ones in the lower fs, which likely did not map into the shifts s_user_ns. A local attacker could use this to possibly bypass discretionary access control permissions.

CVSS v3.0 8.8 HIGH
CVSS v2.0 4.6 MEDIUM

8.8^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 2.0 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

4.6^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 3.9 / Impact : 6.4

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://usn.ubuntu.com/usn/usn-4183-1	Third Party Advisory
https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=3644b9d5688da86f18e017c9c580b75cf52927bb	Mailing List Patch Third Party Advisory
https://usn.ubuntu.com/usn/usn-4184-1	Third Party Advisory

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Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel:5.0:::::::*
	cpe:2.3:o:linux:linux_kernel:5.3:::::::*

Configuration 2 (hide)

OR	cpe:2.3:o:canonical:ubuntu_linux:18.04::::lts:::
	cpe:2.3:o:canonical:ubuntu_linux:19.04:::::::*

Information

Published : 2020-04-23 17:15

Updated : 2020-05-01 07:48

NVD link : CVE-2019-15793

Mitre link : CVE-2019-15793

JSON object : View

CWE

CWE-276

Incorrect Default Permissions

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Products Affected

canonical

ubuntu_linux

linux

linux_kernel

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