CVE-2022-24122
published 2022-01-29CVE-2022-24122: kernel/ucount.c in the Linux kernel 5.14 through 5.16.4, when unprivileged user namespaces are enabled, allows a use-after-free and privilege escalation…
PriorityP341high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
1.01%
59.2th percentile
kernel/ucount.c in the Linux kernel 5.14 through 5.16.4, when unprivileged user namespaces are enabled, allows a use-after-free and privilege escalation because a ucounts object can outlive its namespace.
Affected
11 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.15.15-2 (bookworm) | linux 5.15.15-2 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| linux | linux_kernel | >= 0 < 5.15.15-2 | 5.15.15-2 |
| linux | linux_kernel | >= 0 < 5.15.15-2 | 5.15.15-2 |
| linux | linux_kernel | >= 0 < 5.15.15-2 | 5.15.15-2 |
| linux | linux_kernel | >= 5.14 < 5.15.19 | 5.15.19 |
| linux | linux_kernel | >= 5.16 < 5.16.5 | 5.16.5 |
| msrc | cbl2_kernel_5.15.26.1-1_on_cbl_mariner_2.0 | — | — |
| msrc | cbl_mariner_2.0_arm | — | — |
| msrc | cbl_mariner_2.0_x64 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.06.9MEDIUMAV:L/AC:M/Au:N/C:C/I:C/A:C
osv7.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu4.7MEDIUM
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OSV
linux-oem-5.14 vulnerabilities
osv·2022-02-09·CVSS 4.7
CVE-2022-24122 [MEDIUM] linux-oem-5.14 vulnerabilities
linux-oem-5.14 vulnerabilities
It was discovered that the rlimit tracking for user namespaces in the Linux
kernel did not properly perform reference counting, leading to a use-after-
free vulnerability. A local attacker could use this to cause a denial of
service or possibly execute arbitrary code. (CVE-2022-24122)
It was discovered that the BPF verifier in the Linux kernel did not
properly restrict pointer types in certain situations. A local attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. (CVE-2022-23222)
Jeremy Cline discovered a use-after-free in the nouveau graphics driver of
the Linux kernel during device removal. A privileged or physically
proximate attacker could use this to cause a denial of service (system
crash). (CVE-20
GHSA
GHSA-qffg-f4f5-j77v: kernel/ucount
ghsa_unreviewed·2022-01-30
CVE-2022-24122 [HIGH] CWE-416 GHSA-qffg-f4f5-j77v: kernel/ucount
kernel/ucount.c in the Linux kernel 5.14 through 5.16.4, when unprivileged user namespaces are enabled, allows a use-after-free and privilege escalation because a ucounts object can outlive its namespace.
OSV
CVE-2022-24122: kernel/ucount
osv·2022-01-29·CVSS 7.8
CVE-2022-24122 [HIGH] CVE-2022-24122: kernel/ucount
kernel/ucount.c in the Linux kernel 5.14 through 5.16.4, when unprivileged user namespaces are enabled, allows a use-after-free and privilege escalation because a ucounts object can outlive its namespace.
Ubuntu
Linux kernel (OEM) vulnerabilities
vendor_ubuntu·2022-02-09·CVSS 4.7
CVE-2022-23222 [MEDIUM] Linux kernel (OEM) vulnerabilities
Title: Linux kernel (OEM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that the rlimit tracking for user namespaces in the Linux
kernel did not properly perform reference counting, leading to a use-after-
free vulnerability. A local attacker could use this to cause a denial of
service or possibly execute arbitrary code. (CVE-2022-24122)
It was discovered that the BPF verifier in the Linux kernel did not
properly restrict pointer types in certain situations. A local attacker
could use this to cause a denial of service (system crash) or possibly
execute arbitrary code. (CVE-2022-23222)
Jeremy Cline discovered a use-after-free in the nouveau graphics driver of
the Linux kernel during device removal. A privileged or physically
proximate
Red Hat
kernel: use-after-free and privilege escalation in kernel/ucount.c when unprivileged user namespaces are enabled
vendor_redhat·2022-01-30·CVSS 7.8
CVE-2022-24122 [HIGH] CWE-416 kernel: use-after-free and privilege escalation in kernel/ucount.c when unprivileged user namespaces are enabled
kernel: use-after-free and privilege escalation in kernel/ucount.c when unprivileged user namespaces are enabled
kernel/ucount.c in the Linux kernel 5.14 through 5.16.4, when unprivileged user namespaces are enabled, allows a use-after-free and privilege escalation because a ucounts object can outlive its namespace.
A use-after-free vulnerability was found in the Linux kernel’s alloc_ucounts in the kernel/ucount.c function. This flaw allows a local attacker with unprivileged user namespaces to cause a privilege escalation problem.
Statement: There was no shipped kernel version that was seen affected by this problem. These files are not built in our source code.
Mitigation: To mitigate this problem, disable unprivileged user namespaces:
~~~
# sysctl -w kernel.unprivileged_userns_clone=0
Microsoft
kernel/ucount.c in the Linux kernel 5.14 through 5.16.4 when unprivileged user namespaces are enabled allows a use-after-free and privilege escalation because a ucounts object can outlive its namespac
vendor_msrc·2022-01-11·CVSS 7.8
CVE-2022-24122 [HIGH] CWE-416 kernel/ucount.c in the Linux kernel 5.14 through 5.16.4 when unprivileged user namespaces are enabled allows a use-after-free and privilege escalation because a ucounts object can outlive its namespac
kernel/ucount.c in the Linux kernel 5.14 through 5.16.4 when unprivileged user namespaces are enabled allows a use-after-free and privilege escalation because a ucounts object can outlive its namespace.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update t
Debian
CVE-2022-24122: linux - kernel/ucount.c in the Linux kernel 5.14 through 5.16.4, when unprivileged user ...
vendor_debian·2022·CVSS 7.8
CVE-2022-24122 [HIGH] CVE-2022-24122: linux - kernel/ucount.c in the Linux kernel 5.14 through 5.16.4, when unprivileged user ...
kernel/ucount.c in the Linux kernel 5.14 through 5.16.4, when unprivileged user namespaces are enabled, allows a use-after-free and privilege escalation because a ucounts object can outlive its namespace.
Scope: local
bookworm: resolved (fixed in 5.15.15-2)
bullseye: resolved
forky: resolved (fixed in 5.15.15-2)
sid: resolved (fixed in 5.15.15-2)
trixie: resolved (fixed in 5.15.15-2)
No detection rules found.
No public exploits indexed.
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f9d87929d451d3e649699d0f1d74f71f77ad38f5https://github.com/torvalds/linux/commit/f9d87929d451d3e649699d0f1d74f71f77ad38f5https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HSR3AI2IQGRKZCHNKF6S25JGDKUEAWWL/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VVSZKUJAZ2VN6LJ35J2B6YD6BOPQTU3B/https://security.netapp.com/advisory/ntap-20220221-0001/https://www.openwall.com/lists/oss-security/2022/01/29/1https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f9d87929d451d3e649699d0f1d74f71f77ad38f5https://github.com/torvalds/linux/commit/f9d87929d451d3e649699d0f1d74f71f77ad38f5https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HSR3AI2IQGRKZCHNKF6S25JGDKUEAWWL/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VVSZKUJAZ2VN6LJ35J2B6YD6BOPQTU3B/https://security.netapp.com/advisory/ntap-20220221-0001/https://www.openwall.com/lists/oss-security/2022/01/29/1
2022-01-29
Published