CVE-2021-3493
Vulnerability from cvelistv5
Published
2021-04-17 04:20
Modified
2024-09-17 02:48
Severity ?
EPSS score ?
Summary
The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| ▼ | Ubuntu | linux kernel |
Version: 5.8 kernel < 5.8.0-50.56 Version: 5.4 kernel < 5.4.0-72.80 Version: 4.15 kernel < 4.15.0-142.146 Version: 4.4 kernel < 4.4.0-209.241 |
|
|
|||
CISA Known exploited vulnerability
Data from the Known Exploited Vulnerabilities Catalog
Date added: 2022-10-20
Due date: 2022-11-10
Required action: Apply updates per vendor instructions.
Used in ransomware: Unknown
Notes: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c03e2cda4a584cadc398e8f6641ca9988a39d52; https://nvd.nist.gov/vuln/detail/CVE-2021-3493
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.