Vulnerability · Published Mar 3, 2022 · Assigned by redhat
CVE-2021-4002
Medium 4.4
In plain English
A medium-severity security flaw in kernel. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS NVD)4.4Medium
Exploit odds (30 days)0.5%top 55.9% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known
Official description
A memory leak flaw in the Linux kernel's hugetlbfs memory usage was found in the way the user maps some regions of memory twice using shmget() which are aligned to PUD alignment with the fault of some of the memory pages. A local user could use this flaw to get unauthorized access to some data.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | bpftool | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-abi-stablelists | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-core | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-cross-headers | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-debug | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-debug-core | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-debug-devel | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-debug-modules | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-debug-modules-extra | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-devel | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-doc | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-headers | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-modules | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-modules-extra | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-tools | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-tools-libs | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | kernel-tools-libs-devel | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | perf | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| AlmaLinux:8 | python3-perf | 4.18.0-372.9.1.el8 | ALSA-2022:1988 |
| Debian:12 | linux | 5.15.5-1 | DEBIAN-CVE-2021-4002 |
| Debian:13 | linux | 5.15.5-1 | DEBIAN-CVE-2021-4002 |
| Debian:14 | linux | 5.15.5-1 | DEBIAN-CVE-2021-4002 |
| Rocky Linux:8 | kernel | 0:4.18.0-372.9.1.el8 | RLSA-2022:1988 |
| Rocky Linux:8 | kernel-rt | 0:4.18.0-372.9.1.rt7.166.el8 | RLSA-2022:1975 |
| Ubuntu:22.04:LTS | linux-intel-iot-realtime | no fix listed | UBUNTU-CVE-2021-4002 |
| Ubuntu:24.04:LTS | linux-raspi-realtime | no fix listed | UBUNTU-CVE-2021-4002 |
| Ubuntu:22.04:LTS | linux-realtime | no fix listed | UBUNTU-CVE-2021-4002 |
Affected products (as reported)
Weakness: CWE-459
References
- https://bugzilla.redhat.com/show_bug.cgi?id=2025726 x_refsource_MISC
- https://www.openwall.com/lists/oss-security/2021/11/25/1 x_refsource_MISC
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=13e4ad2ce8df6e058ef482a31fdd81c725b0f7ea x_refsource_MISC
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a4a118f2eead1d6c49e00765de89878288d4b890 x_refsource_MISC
- [debian-lts-announce] 20220309 [SECURITY] [DLA 2940-1] linux security update mailing-list, x_refsource_MLIST
- [debian-lts-announce] 20220309 [SECURITY] [DLA 2941-1] linux-4.19 security update mailing-list, x_refsource_MLIST
- DSA-5096 vendor-advisory, x_refsource_DEBIAN
- https://www.oracle.com/security-alerts/cpujul2022.html x_refsource_MISC