CVE-2021-20317

The Linux Kernel, the operating system core itself.

Security Fix(es):

A flaw was found in the Linux kernel. Measuring usage of the shared memory does not scale with large shared memory segment counts which could lead to resource exhaustion and DoS.(CVE-2021-3669)

(CVE-2021-3764)

(CVE-2021-3744)

arch/mips/net/bpf_jit.c in the Linux kernel before 5.4.10 can generate undesirable machine code when transforming unprivileged cBPF programs, allowing execution of arbitrary code within the kernel context. This occurs because conditional branches can exceed the 128 KB limit of the MIPS architecture.(CVE-2021-38300)

A use-after-free flaw was found in the Linux kernel's Bluetooth subsystem in the way user calls connect to the socket and disconnect simultaneously due to a race condition. This flaw allows a user to crash the system or escalate their privileges. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.(CVE-2021-3752)

A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP.(CVE-2021-20317)

prealloc_elems_and_freelist in kernel/bpf/stackmap.c in the Linux kernel through 5.14.9 allows unprivileged users to trigger an eBPF multiplication integer overflow with a resultant out-of-bounds write.(CVE-2021-41864)

The decode_data function in drivers/net/hamradio/6pack.c in the Linux kernel before 5.13.13 has a slab out-of-bounds write. Input from a process that has the CAP_NET_ADMIN capability can lead to root access.(CVE-2021-42008)

The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.

Security Fix(es):

• kernel: Insufficient validation of user-supplied sizes for the MSG_CRYPTO message type (CVE-2021-43267)

• kernel: timer tree corruption leads to missing wakeup and system freeze (CVE-2021-20317)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Bug Fix(es):

• kernel-rt: update RT source tree to the Rocky Linux-8.5.z source tree (BZ#2020036)

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

• kernel: Insufficient validation of user-supplied sizes for the MSG_CRYPTO message type (CVE-2021-43267)

• kernel: timer tree corruption leads to missing wakeup and system freeze (CVE-2021-20317)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP.

The kernel packages contain the Linux kernel, the core of any Linux operating system.

Security Fix(es):

• kernel: Insufficient validation of user-supplied sizes for the MSG_CRYPTO message type (CVE-2021-43267)

• kernel: timer tree corruption leads to missing wakeup and system freeze (CVE-2021-20317)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Nadav Amit discovered that the hugetlb implementation in the Linux kernel did not perform TLB flushes under certain conditions. A local attacker could use this to leak or alter data from other processes that use huge pages. (CVE-2021-4002)

It was discovered that a race condition existed in the timer implementation in the Linux kernel. A privileged attacker could use this to cause a denial of service. (CVE-2021-20317)

It was discovered that a race condition existed in the overlay file system implementation in the Linux kernel. A local attacker could use this to cause a denial of service (system crash). (CVE-2021-20321)

It was discovered that the NFC subsystem in the Linux kernel contained a use-after-free vulnerability in its NFC Controller Interface (NCI) implementation. A local attacker could possibly use this to cause a denial of service (system crash) or execute arbitrary code. (CVE-2021-3760)

It was discovered that an integer overflow could be triggered in the eBPF implementation in the Linux kernel when preallocating objects for stack maps. A privileged local attacker could use this to cause a denial of service or possibly execute arbitrary code. (CVE-2021-41864)

It was discovered that the ISDN CAPI implementation in the Linux kernel contained a race condition in certain situations that could trigger an array out-of-bounds bug. A privileged local attacker could possibly use this to cause a denial of service or execute arbitrary code. (CVE-2021-43389)

Yiqi Sun and Kevin Wang discovered that the cgroups implementation in the Linux kernel did not properly restrict access to the cgroups v1 release_agent feature. A local attacker could use this to gain administrative privileges. (CVE-2022-0492)

It was discovered that the aufs file system in the Linux kernel did not properly restrict mount namespaces, when mounted with the non-default allow_userns option set. A local attacker could use this to gain administrative privileges. (CVE-2016-2853)

It was discovered that the aufs file system in the Linux kernel did not properly maintain POSIX ACL xattr data, when mounted with the non-default allow_userns option. A local attacker could possibly use this to gain elevated privileges. (CVE-2016-2854)

It was discovered that the f2fs file system in the Linux kernel did not properly validate metadata in some situations. An attacker could use this to construct a malicious f2fs image that, when mounted and operated on, could cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2019-19449)

It was discovered that the XFS file system implementation in the Linux kernel did not properly validate meta data in some circumstances. An attacker could use this to construct a malicious XFS image that, when mounted, could cause a denial of service. (CVE-2020-12655)

Kiyin (尹亮) discovered that the NFC LLCP protocol implementation in the Linux kernel contained a reference counting error. A local attacker could use this to cause a denial of service (system crash). (CVE-2020-25670)

Kiyin (尹亮) discovered that the NFC LLCP protocol implementation in the Linux kernel did not properly deallocate memory in certain error situations. A local attacker could use this to cause a denial of service (memory exhaustion). (CVE-2020-25671, CVE-2020-25672)

Kiyin (尹亮) discovered that the NFC LLCP protocol implementation in the Linux kernel did not properly handle error conditions in some situations, leading to an infinite loop. A local attacker could use this to cause a denial of service. (CVE-2020-25673)

Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation incorrectly handled EAPOL frames from unauthenticated senders. A physically proximate attacker could inject malicious packets to cause a denial of service (system crash). (CVE-2020-26139)

Mathy Vanhoef discovered that the Linux kernel’s WiFi implementation could reassemble mixed encrypted and plaintext fragments. A physically proximate attacker could possibly use this issue to inject packets or exfiltrate selected fragments. (CVE-2020-26147)

It was discovered that the BR/EDR pin-code pairing procedure in the Linux kernel was vulnerable to an impersonation attack. A physically proximate attacker could possibly use this to pair to a device without knowledge of the pin-code. (CVE-2020-26555)

It was discovered that the bluetooth subsystem in the Linux kernel did not properly perform access control. An authenticated attacker could possibly use this to expose sensitive information. (CVE-2020-26558, CVE-2021-0129)

It was discovered that the FUSE user space file system implementation in the Linux kernel did not properly handle bad inodes in some situations. A local attacker could possibly use this to cause a denial of service. (CVE-2020-36322)

It was discovered that the Infiniband RDMA userspace connection manager implementation in the Linux kernel contained a race condition leading to a use-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possible execute arbitrary code. (CVE-2020-36385)

It was discovered that the DRM subsystem in the Linux kernel contained double-free vulnerabilities. A privileged attacker could possibly use this to cause a denial of service (system crash) or possibly execute arbitrary code. (CVE-2021-20292)

It was discovered that a race condition existed in the timer implementation in the Linux kernel. A privileged attacker could use…