CVE-2020-25040: Github.com/sylabs/singularity Insecure Permissions On Build Temporary Vulnerability
HIGHCVE-2020-25040 is a HIGH (CVSS 8.8) insecure permissions on build temporary vulnerability (CWE-668: Exposure of Resource to Wrong Sphere) affecting Github.com/sylabs/singularity libraries in the Go ecosystem. The issue involves insecure permissions on build temporary rootfs in singularity. Remediation is available by upgrading affected packages to version 3.6.3.
CVE-2020-25040 at a Glance
Security Impact
CVSS: 8.8
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
How to Fix CVE-2020-25040
To remediate this vulnerability, upgrade all affected Github.com/sylabs/singularity dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/sylabs/singularity to 3.6.3Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/sylabs/singularityHow to Check if You Are Affected
To determine whether your application is affected by CVE-2020-25040, inspect your project dependencies for Github.com/sylabs/singularity:
inspect dependencies for github.com/sylabs/singularityAnalyze the terminal output to locate any version of Github.com/sylabs/singularity in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.6.3), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-668: Exposure of Resource to Wrong Sphere, where the product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource. In Github.com/sylabs/singularity, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2020-25040 Affected Github.com/sylabs/singularity Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/sylabs/singularity
|
Go |
< 3.6.3
|
3.6.3
|
References
Frequently Asked Questions
What is CVE-2020-25040?
Which Github.com/sylabs/singularity versions are affected?
What version fixes CVE-2020-25040?
Is github.com/sylabs/singularity affected?
What is the CVSS score of CVE-2020-25040?
What CWE is associated with CVE-2020-25040?
How can I check Go dependencies for CVE-2020-25040?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-jv9c-w74q-6762",
"modified" : "2021-05-24T16:53:16Z",
"published" : "2021-05-24T16:56:23Z",
"aliases" : [ "CVE-2020-25040" ],
"summary" : "Insecure permissions on build temporary rootfs in Singularity",
"details" : "### Impact\n\nInsecure permissions on temporary directories used in explicit and implicit container build operations.\n\nWhen a Singularity command that results in a container build operation is executed, it is possible for a user with access to the system to read the contents of the image during the build. Additionally, if the image contains a world-writable file or directory, it is possible for a user to inject arbitrary content into the running build, which in certain circumstances may enable arbitrary code execution during the build and/or when the built container is run.\n\n### Patches\n\nThis issue is addressed in Singularity 3.6.3.\n\nAll users are advised to upgrade to 3.6.3.\n\n### Workarounds\n\nThe issue is mitigated if `TMPDIR` is set to a location that is only accessible to the user, as any subdirectories directly under `TMPDIR` cannot then be accessed by others. However, this is difficult to enforce so it is not recommended to rely on this as a mitigation.\n\n### For more information\n\nGeneral questions about the impact of the advisory / changes made in the 3.6.0 release can be asked in the:\n\n* [Singularity Slack Channel](https://bit.ly/2m0g3lX)\n* [Singularity Mailing List](https://groups.google.com/a/lbl.gov/forum/??sdf%7Csort:date#!forum/singularity)\n\nAny sensitive security concerns should be directed to: security@sylabs.io\n\nSee our Security Policy here: https://sylabs.io/security-policy",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/sylabs/singularity"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "3.6.3"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/hpcng/singularity/security/advisories/GHSA-jv9c-w74q-6762"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-25040"
}, {
"type" : "WEB",
"url" : "https://medium.com/sylabs"
}, {
"type" : "WEB",
"url" : "http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00070.html"
}, {
"type" : "WEB",
"url" : "http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00088.html"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-668", "CWE-732" ],
"severity" : "HIGH",
"github_reviewed" : true,
"github_reviewed_at" : "2021-05-24T16:53:16Z",
"nvd_published_at" : "2020-09-16T18:15:00Z"
}
}