{"id":"CVE-2020-25040","aliases":["GHSA-jv9c-w74q-6762"],"title":"Insecure permissions on build temporary rootfs in Singularity","summary":"Insecure permissions on build temporary rootfs in Singularity","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","vendor":"sylabs","product":"github.com/sylabs/singularity","ecosystem":"go","affected":["github.com/sylabs/singularity < 3.6.3"],"patched":["github.com/sylabs/singularity 3.6.3"],"published":"2021-05-24","updated":"2026-07-08","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-jv9c-w74q-6762","references":[{"url":"https://github.com/hpcng/singularity/security/advisories/GHSA-jv9c-w74q-6762"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-25040"},{"url":"https://medium.com/sylabs"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00070.html"},{"url":"http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00088.html"}],"tags":["osv","go"],"epss":0.0204,"epssPercentile":0.80274,"ingestedAt":"2026-07-09T18:56:36.595Z","slug":"CVE-2020-25040","body":"## Overview\n\n### 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\n\n## Affected packages\n\n- `github.com/sylabs/singularity < 3.6.3`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `github.com/sylabs/singularity 3.6.3`","depth":"twilight","depthScore":49,"depthScoreParts":{"impact":48.4,"likelihood":0.4,"exploitation":0,"ransomware":0},"changes":[]}