Summary
Jann Horn discovered that the tty subsystem of the Linux kernel did not use
consistent locking in some situations, leading to a read-after-free
vulnerability. A local attacker could use this to cause a denial of service
(system crash) or possibly expose sensitive information (kernel memory).(CVE-2020-29660)
Jann Horn discovered a race condition in the tty subsystem of the Linux
kernel in the locking for the TIOCSPGRP ioctl(), leading to a use-after-
free vulnerability. A local attacker could use this to cause a denial of
service (system crash) or possibly execute arbitrary code.(CVE-2020-29661)
De4dCr0w of 360 Alpha Lab discovered that the BPF verifier in the Linux
kernel did not properly handle mod32 destination register truncation when
the source register was known to be 0. A local attacker could use this to
expose sensitive information (kernel memory) or possibly execute arbitrary
code.(CVE-2021-3444)
kernel: use-after-free in route4_change() in
net/sched/cls_route.c(CVE-2021-3715)
Fixed packages 12
| Release | Package | Fixed in |
|---|---|---|
| Ubuntu · Pro 16.04 LTS Pro:16.04:LTS | linux | 4.4.0-203.235 |
| Ubuntu · Pro 16.04 LTS Pro:16.04:LTS | linux-hwe | 4.15.0-136.140~16.04.1 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | linux | 4.15.0-136.140 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | linux-gke-4.15 | 4.15.0-1079.84 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | linux-gke-5.4 | 5.4.0-1039.41~18.04.1 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | linux-gkeop-5.4 | 5.4.0-1012.13~18.04.1 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | linux-hwe-5.4 | 5.4.0-70.78~18.04.1 |
| Ubuntu · Pro 18.04 LTS Pro:18.04:LTS | linux-oem | — |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux | 5.4.0-70.78 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-gcp | 5.4.0-1040.43 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-gke | 5.4.0-1039.41 |
| Ubuntu · Pro 20.04 LTS Pro:20.04:LTS | linux-gkeop | 5.4.0-1012.13 |
Vulnerabilities 4
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High 7.8
Linux kernel bpf verifier incorrect mod32 truncation
The bpf verifier in the Linux kernel did not properly handle mod32 destination register truncation when the source register was known to be 0. A local attacker with the ability to load bpf programs could use this gain out-of-bounds reads in kernel memory lead…
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Unscored —
A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel through 5.9.13. drivers/tty/tty_i…
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Unscored —CVE-2020-29661 Public exploit
A locking issue was discovered in the tty subsystem of the Linux kernel through 5.9.13. drivers/tty/tty_jobctrl.c allow…
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Unscored —
A flaw was found in the "Routing decision" classifier in the Linux kernel's Traffic Control networking subsystem in the…