9.3 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
5.8 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:N/C:P/I:P/A:N
0.002 Low
EPSS
Percentile
64.2%
Due to insecure handling of path traversal and the lack of path sanitization within unsquashfs
(a distribution provided utility used by Singularity), it is possible to overwrite/create any files on the host filesystem during the extraction of a crafted squashfs filesystem.
Squashfs extraction occurs automatically for unprivileged execution of Singularity (either --without-suid
installation or with allow setuid = no
) when a user attempts to run an image which:
library://
or shub://
Image build is also impacted in a more serious way as it is often performed by the root user, allowing an attacker to overwrite/create files leading to a system compromise. Bootstrap methods library
, shub
and localimage
trigger a squashfs extraction.
This issue is addressed in Singularity 3.6.4.
All users are advised to upgrade to 3.6.4 especially if they use Singularity mainly for building image as root user.
There is no solid workaround except to temporarily avoid use of unprivileged mode with single file images, in favor of sandbox images instead. Regarding image build, temporarily avoid building from library
and shub
sources, and as much as possible use --fakeroot
or a VM to limit potential impact.
General questions about the impact of the advisory / changes made in the 3.6.0 release can be asked in the:
Any sensitive security concerns should be directed to: [email protected]
See our Security Policy here: https://sylabs.io/security-policy
CPE | Name | Operator | Version |
---|---|---|---|
github.com/sylabs/singularity | lt | 3.6.4 |
lists.opensuse.org/opensuse-security-announce/2020-10/msg00070.html
lists.opensuse.org/opensuse-security-announce/2020-10/msg00071.html
lists.opensuse.org/opensuse-security-announce/2020-11/msg00009.html
github.com/advisories/GHSA-7gcp-w6ww-2xv9
github.com/hpcng/singularity/blob/v3.6.4/CHANGELOG.md#security-related-fixes
github.com/hpcng/singularity/commit/eba3dea260b117198fdb6faf41f2482ab2f8d53e
github.com/hpcng/singularity/pull/5611
github.com/hpcng/singularity/security/advisories/GHSA-7gcp-w6ww-2xv9
nvd.nist.gov/vuln/detail/CVE-2020-15229
9.3 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
5.8 Medium
CVSS2
Access Vector
NETWORK
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:N/C:P/I:P/A:N
0.002 Low
EPSS
Percentile
64.2%