CVE-2021-38166
published 2021-08-07CVE-2021-38166: In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer overflow and out-of-bounds write when many elements are placed in a single…
PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.32%
24.0th percentile
In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket. NOTE: exploitation might be impractical without the CAP_SYS_ADMIN capability.
Affected
11 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | linux | < linux 5.14.6-1 (bookworm) | linux 5.14.6-1 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| linux | linux_kernel | <= 5.13.8 | — |
| linux | linux_kernel | >= 0 < 5.10.46-5 | 5.10.46-5 |
| linux | linux_kernel | >= 0 < 5.14.6-1 | 5.14.6-1 |
| linux | linux_kernel | >= 0 < 5.14.6-1 | 5.14.6-1 |
| linux | linux_kernel | >= 0 < 5.14.6-1 | 5.14.6-1 |
| msrc | cbl2_kernel_5.10.78.1-1_on_cbl_mariner_2.0 | — | — |
| msrc | cm1_kernel_5.10.60.1-1_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
nvdv2.04.6MEDIUMAV:L/AC:L/Au:N/C:P/I:P/A:P
osv7.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu6.5MEDIUM
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GHSA
GHSA-cg35-fr7p-33m9: In kernel/bpf/hashtab
ghsa_unreviewed·2022-05-24
CVE-2021-38166 [HIGH] CWE-787 GHSA-cg35-fr7p-33m9: In kernel/bpf/hashtab
In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket. NOTE: exploitation might be impractical without the CAP_SYS_ADMIN capability.
OSV
linux-oem-5.10 vulnerabilities
osv·2021-10-20·CVSS 6.5
CVE-2020-3702 [MEDIUM] linux-oem-5.10 vulnerabilities
linux-oem-5.10 vulnerabilities
It was discovered that a race condition existed in the Atheros Ath9k WiFi
driver in the Linux kernel. An attacker could possibly use this to expose
sensitive information (WiFi network traffic). (CVE-2020-3702)
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 sensitive information. (CVE-2021-345
OSV
linux, linux-aws, linux-aws-5.11, linux-azure, linux-azure-5.11, linux-gcp, linux-gcp-5.11, linux-hwe-5.11, linux-kvm, linux-oracle, linux-oracle-5.11, linux-raspi vulnerabilities
osv·2021-10-19·CVSS 6.5
CVE-2020-3702 [MEDIUM] linux, linux-aws, linux-aws-5.11, linux-azure, linux-azure-5.11, linux-gcp, linux-gcp-5.11, linux-hwe-5.11, linux-kvm, linux-oracle, linux-oracle-5.11, linux-raspi vulnerabilities
linux, linux-aws, linux-aws-5.11, linux-azure, linux-azure-5.11, linux-gcp, linux-gcp-5.11, linux-hwe-5.11, linux-kvm, linux-oracle, linux-oracle-5.11, linux-raspi vulnerabilities
It was discovered that a race condition existed in the Atheros Ath9k WiFi
driver in the Linux kernel. An attacker could possibly use this to expose
sensitive information (WiFi network traffic). (CVE-2020-3702)
Alois Wohlschlager discovered that the overlay file system in the Linux
kernel did not restrict private clones in some situations. An attacker
could use this to expose sensitive information. (CVE-2021-3732)
It was discovered that the btrfs file system in the Linux kernel did not
properly handle removing a non-existent device id. An attacker with
CAP_SYS_ADMIN could use this to cause a denial of service.
OSV
CVE-2021-38166: In __htab_map_lookup_and_delete_batch of hashtab
osv·2021-10-01
CVE-2021-38166 CVE-2021-38166: In __htab_map_lookup_and_delete_batch of hashtab
In __htab_map_lookup_and_delete_batch of hashtab.c, there is a possible out of bounds write due to an integer overflow. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation.
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
CVE-2021-38166: In kernel/bpf/hashtab
osv·2021-08-07·CVSS 7.8
CVE-2021-38166 [HIGH] CVE-2021-38166: In kernel/bpf/hashtab
In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket. NOTE: exploitation might be impractical without the CAP_SYS_ADMIN capability.
Ubuntu
Linux kernel (OEM) vulnerabilities
vendor_ubuntu·2021-10-20·CVSS 6.5
CVE-2021-3679 [MEDIUM] Linux kernel (OEM) vulnerabilities
Title: Linux kernel (OEM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that a race condition existed in the Atheros Ath9k WiFi
driver in the Linux kernel. An attacker could possibly use this to expose
sensitive information (WiFi network traffic). (CVE-2020-3702)
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 at
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2021-10-19·CVSS 6.5
CVE-2021-42008 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that a race condition existed in the Atheros Ath9k WiFi
driver in the Linux kernel. An attacker could possibly use this to expose
sensitive information (WiFi network traffic). (CVE-2020-3702)
Alois Wohlschlager discovered that the overlay file system in the Linux
kernel did not restrict private clones in some situations. An attacker
could use this to expose sensitive information. (CVE-2021-3732)
It was discovered that the btrfs file system in the Linux kernel did not
properly handle removing a non-existent device id. An attacker with
CAP_SYS_ADMIN could use this to cause a denial of service. (CVE-2021-3739)
It was discovered that the Qualcomm IPC Router protocol imple
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
Microsoft
In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8 there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket. NOTE: exploitation might be impractica
vendor_msrc·2021-08-10·CVSS 7.8
CVE-2021-38166 [HIGH] CWE-787 In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8 there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket. NOTE: exploitation might be impractica
In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8 there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket. NOTE: exploitation might be impractical without the CAP_SYS_ADMIN capability.
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 pro
Red Hat
kernel: integer overflow and out-of-bounds write in kernel/bpf/hashtab.c when many elements are placed in a single bucket
vendor_redhat·2021-08-07·CVSS 7.8
CVE-2021-38166 [HIGH] CWE-787 kernel: integer overflow and out-of-bounds write in kernel/bpf/hashtab.c when many elements are placed in a single bucket
kernel: integer overflow and out-of-bounds write in kernel/bpf/hashtab.c when many elements are placed in a single bucket
In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket. NOTE: exploitation might be impractical without the CAP_SYS_ADMIN capability.
A flaw was found in the Linux kernel. An integer overflow can allow an out-of-bounds write when many elements are placed in a hash's bucket. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Mitigation: The default Red Hat Enterprise Linux kernel setting prevents unprivileged users from being able to use eBPF via the kernel.unprivileged_bpf_disabled sysctl. As such,
Debian
CVE-2021-38166: linux - In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer ...
vendor_debian·2021·CVSS 7.8
CVE-2021-38166 [HIGH] CVE-2021-38166: linux - In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer ...
In kernel/bpf/hashtab.c in the Linux kernel through 5.13.8, there is an integer overflow and out-of-bounds write when many elements are placed in a single bucket. NOTE: exploitation might be impractical without the CAP_SYS_ADMIN capability.
Scope: local
bookworm: resolved (fixed in 5.14.6-1)
bullseye: resolved (fixed in 5.10.46-5)
forky: resolved (fixed in 5.14.6-1)
sid: resolved (fixed in 5.14.6-1)
trixie: resolved (fixed in 5.14.6-1)
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=c4eb1f403243fc7bbb7de644db8587c03de36da6https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GUVLBJKZMWA3E3YXSH4SZ7BOYGJP4GXP/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UL6CH5M5PRLMA3KPBX4LPUO6Z73GRISO/https://lore.kernel.org/bpf/20210806150419.109658-1-th.yasumatsu%40gmail.com/https://security.netapp.com/advisory/ntap-20210909-0001/https://www.debian.org/security/2021/dsa-4978https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=c4eb1f403243fc7bbb7de644db8587c03de36da6https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GUVLBJKZMWA3E3YXSH4SZ7BOYGJP4GXP/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UL6CH5M5PRLMA3KPBX4LPUO6Z73GRISO/https://lore.kernel.org/bpf/20210806150419.109658-1-th.yasumatsu%40gmail.com/https://security.netapp.com/advisory/ntap-20210909-0001/https://www.debian.org/security/2021/dsa-4978
2021-08-07
Published