CVE-2021-41073
published 2021-09-19CVE-2021-41073: loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a…
PriorityP345high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
1.72%
75.1th percentile
loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by using /proc//maps for exploitation.
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | linux | < linux 5.14.6-2 (bookworm) | linux 5.14.6-2 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| linux | linux_kernel | >= 0 < 5.10.46-5 | 5.10.46-5 |
| linux | linux_kernel | >= 0 < 5.14.6-2 | 5.14.6-2 |
| linux | linux_kernel | >= 0 < 5.14.6-2 | 5.14.6-2 |
| linux | linux_kernel | >= 0 < 5.14.6-2 | 5.14.6-2 |
| linux | linux_kernel | >= 5.10 < 5.10.68 | 5.10.68 |
| linux | linux_kernel | >= 5.11 < 5.14.7 | 5.14.7 |
| msrc | cbl2_kernel_5.10.78.1-1_on_cbl_mariner_2.0 | — | — |
| msrc | cm1_kernel_5.10.74.1-1_on_cbl_mariner_1.0 | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.2HIGHAV:L/AC:L/Au:N/C:C/I:C/A:C
osv7.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu6.5MEDIUM
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Ubuntu
Linux kernel (Azure) regression
vendor_ubuntu·2021-10-18·CVSS 4.7
[MEDIUM] Linux kernel (Azure) regression
Title: Linux kernel (Azure) regression
Summary: USN-5092-2 introduced a regression in the Linux kernel for Microsoft
Azure cloud systems.
USN-5092-2 fixed vulnerabilities in Linux 5.11-based kernels.
Unfortunately, for Linux kernels intended for use within Microsoft
Azure environments, that update introduced a regression that could
cause the kernel to fail to boot in large Azure instance types.
This update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
Valentina Palmiotti discovered that the io_uring subsystem in the Linux
kernel could be coerced to free adjacent memory. A local attacker could use
this to execute arbitrary code. (CVE-2021-41073)
Ofek Kirzner, Adam Morrison, Benedict Schlueter, and Piotr Krysiuk
discovered that the BPF verifier in th
Ubuntu
Linux kernel (OEM) vulnerabilities
vendor_ubuntu·2021-10-06·CVSS 6.5
CVE-2021-22543 [MEDIUM] Linux kernel (OEM) vulnerabilities
Title: Linux kernel (OEM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Valentina Palmiotti discovered that the io_uring subsystem in the Linux
kernel could be coerced to free adjacent memory. A local attacker could use
this to execute arbitrary code. (CVE-2021-41073)
It was discovered that the Linux kernel did not properly enforce certain
types of entries in the Secure Boot Forbidden Signature Database (aka dbx)
protection mechanism. An attacker could use this to bypass UEFI Secure Boot
restrictions. (CVE-2020-26541)
It was discovered that the KVM hypervisor implementation in the Linux
kernel did not properly perform reference counting in some situations,
leading to a use-after-free vulnerability. An attacker who could start and
control a VM could po
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2021-09-29·CVSS 4.7
CVE-2021-41073 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Valentina Palmiotti discovered that the io_uring subsystem in the Linux
kernel could be coerced to free adjacent memory. A local attacker could use
this to execute arbitrary code. (CVE-2021-41073)
Ofek Kirzner, Adam Morrison, Benedict Schlueter, and Piotr Krysiuk
discovered that the BPF verifier in the Linux kernel missed possible
mispredicted branches due to type confusion, allowing a side-channel
attack. An attacker could use this to expose sensitive information.
(CVE-2021-33624)
Benedict Schlueter discovered that the BPF subsystem in the Linux kernel
did not properly protect against Speculative Store Bypass (SSB) side-
channel attacks in some situations. A local attacker could possib
Ubuntu
Linux kernel (OEM) vulnerabilities
vendor_ubuntu·2021-09-29·CVSS 5.5
CVE-2021-38204 [MEDIUM] Linux kernel (OEM) vulnerabilities
Title: Linux kernel (OEM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Valentina Palmiotti discovered that the io_uring subsystem in the Linux
kernel could be coerced to free adjacent memory. A local attacker could use
this to execute arbitrary code. (CVE-2021-41073)
Benedict Schlueter discovered that the BPF subsystem in the Linux kernel
did not properly protect against Speculative Store Bypass (SSB) side-
channel attacks in some situations. A local attacker could possibly use
this to expose sensitive information. (CVE-2021-34556)
Piotr Krysiuk discovered that the BPF subsystem in the Linux kernel did not
properly protect against Speculative Store Bypass (SSB) side-channel
attacks in some situations. A local attacker could possibly use this to
expos
Red Hat
kernel: local user privilege escalation via loop_rw_iter in fs/io_uring.c
vendor_redhat·2021-09-19·CVSS 7.8
CVE-2021-41073 [HIGH] CWE-119 kernel: local user privilege escalation via loop_rw_iter in fs/io_uring.c
kernel: local user privilege escalation via loop_rw_iter in fs/io_uring.c
loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by using /proc//maps for exploitation.
A flaw was found in loop_rw_iter in fs/io_uring.c in the Linux kernel. This problem gives the ability to a local user with a normal user privilege to free a user-defined kernel space buffer.
Statement: There was no shipped kernel version that was seen affected by this problem. These files are not built in our source code.
Mitigation: Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease
Microsoft
loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer as demonstrated by u
vendor_msrc·2021-09-14·CVSS 7.8
CVE-2021-41073 [HIGH] CWE-763 loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer as demonstrated by u
loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer as demonstrated by using /proc//maps for exploitation.
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
Debian
CVE-2021-41073: linux - loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows loc...
vendor_debian·2021·CVSS 7.8
CVE-2021-41073 [HIGH] CVE-2021-41073: linux - loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows loc...
loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by using /proc//maps for exploitation.
Scope: local
bookworm: resolved (fixed in 5.14.6-2)
bullseye: resolved (fixed in 5.10.46-5)
forky: resolved (fixed in 5.14.6-2)
sid: resolved (fixed in 5.14.6-2)
trixie: resolved (fixed in 5.14.6-2)
GHSA
GHSA-5cqf-vv6j-6f4g: loop_rw_iter in fs/io_uring
ghsa_unreviewed·2022-05-24
CVE-2021-41073 [HIGH] CWE-269 GHSA-5cqf-vv6j-6f4g: loop_rw_iter in fs/io_uring
loop_rw_iter in fs/io_uring.c in the Linux kernel through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by using /proc//maps for exploitation.
OSV
linux-azure, linux-azure-5.11 regression
osv·2021-10-18·CVSS 4.7
[MEDIUM] linux-azure, linux-azure-5.11 regression
linux-azure, linux-azure-5.11 regression
USN-5092-2 fixed vulnerabilities in Linux 5.11-based kernels.
Unfortunately, for Linux kernels intended for use within Microsoft
Azure environments, that update introduced a regression that could
cause the kernel to fail to boot in large Azure instance types.
This update fixes the problem.
We apologize for the inconvenience.
Original advisory details:
Valentina Palmiotti discovered that the io_uring subsystem in the Linux
kernel could be coerced to free adjacent memory. A local attacker could use
this to execute arbitrary code. (CVE-2021-41073)
Ofek Kirzner, Adam Morrison, Benedict Schlueter, and Piotr Krysiuk
discovered that the BPF verifier in the Linux kernel missed possible
mispredicted branches due to type confusion, allowing a side-channe
OSV
linux-oem-5.10 vulnerabilities
osv·2021-10-06·CVSS 6.5
CVE-2021-41073 [MEDIUM] linux-oem-5.10 vulnerabilities
linux-oem-5.10 vulnerabilities
Valentina Palmiotti discovered that the io_uring subsystem in the Linux
kernel could be coerced to free adjacent memory. A local attacker could use
this to execute arbitrary code. (CVE-2021-41073)
It was discovered that the Linux kernel did not properly enforce certain
types of entries in the Secure Boot Forbidden Signature Database (aka dbx)
protection mechanism. An attacker could use this to bypass UEFI Secure Boot
restrictions. (CVE-2020-26541)
It was discovered that the KVM hypervisor implementation in the Linux
kernel did not properly perform reference counting in some situations,
leading to a use-after-free vulnerability. An attacker who could start and
control a VM could possibly use this to expose sensitive information or
execute arbitrary code. (C
OSV
linux-hwe-5.11, linux-azure, linux-azure-5.11, linux-oracle-5.11 vulnerabilities
osv·2021-09-29·CVSS 4.7
CVE-2021-41073 [MEDIUM] linux-hwe-5.11, linux-azure, linux-azure-5.11, linux-oracle-5.11 vulnerabilities
linux-hwe-5.11, linux-azure, linux-azure-5.11, linux-oracle-5.11 vulnerabilities
Valentina Palmiotti discovered that the io_uring subsystem in the Linux
kernel could be coerced to free adjacent memory. A local attacker could use
this to execute arbitrary code. (CVE-2021-41073)
Ofek Kirzner, Adam Morrison, Benedict Schlueter, and Piotr Krysiuk
discovered that the BPF verifier in the Linux kernel missed possible
mispredicted branches due to type confusion, allowing a side-channel
attack. An attacker could use this to expose sensitive information.
(CVE-2021-33624)
Benedict Schlueter discovered that the BPF subsystem in the Linux kernel
did not properly protect against Speculative Store Bypass (SSB) side-
channel attacks in some situations. A local attacker could possibly use
this to expose
OSV
linux-oem-5.13 vulnerabilities
osv·2021-09-29·CVSS 5.5
CVE-2021-41073 [MEDIUM] linux-oem-5.13 vulnerabilities
linux-oem-5.13 vulnerabilities
Valentina Palmiotti discovered that the io_uring subsystem in the Linux
kernel could be coerced to free adjacent memory. A local attacker could use
this to execute arbitrary code. (CVE-2021-41073)
Benedict Schlueter discovered that the BPF subsystem in the Linux kernel
did not properly protect against Speculative Store Bypass (SSB) side-
channel attacks in some situations. A local attacker could possibly use
this to expose sensitive information. (CVE-2021-34556)
Piotr Krysiuk discovered that the BPF subsystem in the Linux kernel did not
properly protect against Speculative Store Bypass (SSB) side-channel
attacks in some situations. A local attacker could possibly use this to
expose sensitive information. (CVE-2021-35477)
Murray McAllister discovered that
OSV
linux, linux-aws, linux-aws-5.11, linux-gcp, linux-kvm, linux-oracle, linux-raspi vulnerabilities
osv·2021-09-28·CVSS 4.7
CVE-2021-41073 [MEDIUM] linux, linux-aws, linux-aws-5.11, linux-gcp, linux-kvm, linux-oracle, linux-raspi vulnerabilities
linux, linux-aws, linux-aws-5.11, linux-gcp, linux-kvm, linux-oracle, linux-raspi vulnerabilities
Valentina Palmiotti discovered that the io_uring subsystem in the Linux
kernel could be coerced to free adjacent memory. A local attacker could use
this to execute arbitrary code. (CVE-2021-41073)
Ofek Kirzner, Adam Morrison, Benedict Schlueter, and Piotr Krysiuk
discovered that the BPF verifier in the Linux kernel missed possible
mispredicted branches due to type confusion, allowing a side-channel
attack. An attacker could use this to expose sensitive information.
(CVE-2021-33624)
Benedict Schlueter discovered that the BPF subsystem in the Linux kernel
did not properly protect against Speculative Store Bypass (SSB) side-
channel attacks in some situations. A local attacker could possibly u
OSV
CVE-2021-41073: loop_rw_iter in fs/io_uring
osv·2021-09-19·CVSS 7.8
CVE-2021-41073 [HIGH] CVE-2021-41073: loop_rw_iter in fs/io_uring
loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by using /proc//maps for exploitation.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
http://www.openwall.com/lists/oss-security/2021/09/18/2http://www.openwall.com/lists/oss-security/2021/09/18/2http://www.openwall.com/lists/oss-security/2022/06/04/4https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=16c8d2df7ec0eed31b7d3b61cb13206a7fb930cchttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/J7KSMIOQ4377CVTHMWNGNCWHMCRFRP2T/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAP4TXEZ7J4EZQMQW5SIJMWXG7WZT3F7/https://security.netapp.com/advisory/ntap-20211014-0003/https://www.debian.org/security/2021/dsa-4978http://www.openwall.com/lists/oss-security/2021/09/18/2http://www.openwall.com/lists/oss-security/2021/09/18/2http://www.openwall.com/lists/oss-security/2022/06/04/4https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=16c8d2df7ec0eed31b7d3b61cb13206a7fb930cchttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/J7KSMIOQ4377CVTHMWNGNCWHMCRFRP2T/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PAP4TXEZ7J4EZQMQW5SIJMWXG7WZT3F7/https://security.netapp.com/advisory/ntap-20211014-0003/https://www.debian.org/security/2021/dsa-4978
2021-09-19
Published