kernel: use after free in tun_get_user of tun.c could lead to local escalation of privilege
Published Jan 11, 2021
6.7
MEDIUMCVSS 3.1
EPSS 0.17%
Description
In tun_get_user of tun.c, there is possible memory corruption due to a use after free. This could lead to local escalation of privilege with System execution privileges required. User interaction is not required for exploitation. Product: Android; Versions: Android kernel; Android ID: A-146554327.
Affected products
- Vendor n/a Product Android Defaultn/a
- Version Android kernelStatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| n/a | Android | n/a |
|
No data.
Red Hat Enterprise Linux 8
kernel-0:4.18.0-305.el8
Fixed · RHSA-2021:1578
Red Hat Enterprise Linux 8
kernel-rt-0:4.18.0-305.rt7.72.el8
Fixed · RHSA-2021:1739
Red Hat Enterprise Linux 6
kernel
Not affected
Red Hat Enterprise Linux 7
kernel
Not affected
Red Hat Enterprise Linux 7
kernel-alt
Not affected
Red Hat Enterprise Linux 7
kernel-rt
Not affected
Red Hat Enterprise Linux 9
kernel
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 8 | kernel-0:4.18.0-305.el8 | Fixed | RHSA-2021:1578 |
| Red Hat Enterprise Linux 8 | kernel-rt-0:4.18.0-305.rt7.72.el8 | Fixed | RHSA-2021:1739 |
| Red Hat Enterprise Linux 6 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel-alt | Not affected | n/a |
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | n/a |
| Red Hat Enterprise Linux 9 | kernel | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This flaw is rated as having Moderate impact because of the need to have elevated privileges and non-standard configuration of the networking device.
Red Hat mitigation
To mitigate this issue, prevent the module tun from being loaded. Please see https://access.redhat.com/solutions/41278 for information on how to blacklist a kernel module to prevent it from loading automatically.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
AV:L/AC:L/Au:N/C:P/I:P/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Table of values (9 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 0.17% (0.00172) | 5.95th | v5 (v2026.06.15) |
| Sep 20, 2026 | 0.17% (0.00172) | 6.92th | v5 (v2026.06.15) |
| Jul 20, 2024 | 0.04% (0.00042) | 5.06th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.04% (0.00042) | 5.63th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.04% (0.01036) | 43.31th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.04% (0.01036) | 39.16th | v2 (v2022.01.01) |
| Feb 4, 2022 | 2.76% (0.02763) | 63.78th | v2 (v2022.01.01) |
| Feb 3, 2022 | 0.58% (0.00585) | 13.43th | v5 (v2026.06.15) |
| Apr 14, 2021 | 0.13% (0.00131) | 0.00th | v1 |
References (6)
- https://access.redhat.com/security/cve/CVE-2021-0342 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1915799 Issue Tracking
- https://lore.kernel.org/netdev/20200608230607.3361041-84-sashal@kernel.org/
- https://nvd.nist.gov/vuln/detail/CVE-2021-0342
- https://source.android.com/security/bulletin/pixel/2021-01-01 x_refsource_CONFIRMPatchVendor Advisory
- https://www.cve.org/CVERecord?id=CVE-2021-0342
| Link | Providers | Tags |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2021-0342 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1915799 | Issue Tracking | |
| https://lore.kernel.org/netdev/20200608230607.3361041-84-sashal@kernel.org/ | ||
| https://nvd.nist.gov/vuln/detail/CVE-2021-0342 | ||
| https://source.android.com/security/bulletin/pixel/2021-01-01 | x_refsource_CONFIRMPatchVendor Advisory | |
| https://www.cve.org/CVERecord?id=CVE-2021-0342 |
Change history (0)
No recorded changes yet.