CVE-2020-29661
Vulnerability Summary
Timeline
Description
A locking issue was discovered in the tty subsystem of the Linux kernel through 5.9.13. drivers/tty/tty_jobctrl.c allows a use-after-free attack against TIOCSPGRP, aka CID-54ffccbf053b.
CVSS Metrics
- v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- v2.0•HIGH•Score: 7.2AV:L/AC:L/Au:N/C:C/I:C/A:C
EPSS Trends
Current EPSS score: 1.12%• Percentile: 65%
Techniques & Countermeasures
- CWE-416•Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
- CWE-667•Improper Locking
The product does not properly acquire or release a lock on a resource, leading to unexpected resource state changes and behaviors.
Affected Systems
- broadcom•fabric_operating_system
na
- debian•linux
< 5.9.15-1 | < 5.9.15-1 | < 5.9.15-1 | < 5.9.15-1
- ubuntu•linux
< 3.13.0-188.239 | < 4.4.0-203.235 | < 4.15.0-136.140 | < 5.4.0-66.74
- ubuntu•linux-aws
< 4.4.0-1086.90 | < 4.4.0-1122.136 | < 4.15.0-1094.101 | < 5.4.0-1038.40
- ubuntu•linux-aws-5.0
all
- ubuntu•linux-aws-5.3
all
- ubuntu•linux-aws-5.4
< 5.4.0-1038.40~18.04.1
- ubuntu•linux-aws-fips
< 4.15.0-2037.39 | all | < 5.4.0-1069.73+fips2
- ubuntu•linux-aws-hwe
< 4.15.0-1094.101~16.04.1
- ubuntu•linux-azure
< 4.15.0-1108.120~14.04.1 | < 4.15.0-1108.120~16.04.1 | all | < 5.4.0-1040.42
- ubuntu•linux-azure-4.15
< 4.15.0-1108.120
- ubuntu•linux-azure-5.3
all
- ubuntu•linux-azure-5.4
< 5.4.0-1040.42~18.04.1
- ubuntu•linux-azure-edge
all
- ubuntu•linux-azure-fips
< 4.15.0-2020.23 | all | < 5.4.0-1073.76+fips1
- ubuntu•linux-bluefield
all
- ubuntu•linux-dell300x
< 4.15.0-1012.16
- ubuntu•linux-fips
< 4.4.0-1056.62 | all | < 4.15.0-1053.61
- ubuntu•linux-gcp
< 4.15.0-1093.106~16.04.1 | all | < 5.4.0-1037.40
- ubuntu•linux-gcp-4.15
< 4.15.0-1093.106
- ubuntu•linux-gcp-5.3
all
- ubuntu•linux-gcp-5.4
< 5.4.0-1037.40~18.04.1
- ubuntu•linux-gcp-edge
all
- ubuntu•linux-gcp-fips
all | < 5.4.0-1067.71~20.04.1
- ubuntu•linux-gke
< 5.4.0-1036.38
- ubuntu•linux-gke-4.15
< 4.15.0-1079.84
- ubuntu•linux-gke-5.4
< 5.4.0-1036.38~18.04.1
- ubuntu•linux-gkeop
< 5.4.0-1010.11
- ubuntu•linux-gkeop-5.4
< 5.4.0-1010.11~18.04.1
- ubuntu•linux-hwe
< 4.15.0-136.140~16.04.1 | all
- ubuntu•linux-hwe-5.4
< 5.4.0-66.74~18.04.2
- ubuntu•linux-hwe-5.8
< 5.8.0-44.50~20.04.1
- ubuntu•linux-hwe-edge
all | all
- ubuntu•linux-intel-iot-realtime
all
- ubuntu•linux-kvm
< 4.4.0-1088.97 | < 4.15.0-1085.87 | < 5.4.0-1033.34
- ubuntu•linux-lts-xenial
< 4.4.0-203.235~14.04.1
- ubuntu•linux-oem
all
- ubuntu•linux-oem-5.6
< 5.6.0-1048.52
- ubuntu•linux-oracle
< 4.15.0-1065.73~16.04.1 | < 4.15.0-1065.73 | < 5.4.0-1038.41
- ubuntu•linux-oracle-5.0
all
- ubuntu•linux-oracle-5.3
all
- ubuntu•linux-oracle-5.4
< 5.4.0-1038.41~18.04.1
- ubuntu•linux-raspi
< 5.4.0-1029.32
- ubuntu•linux-raspi-5.4
< 5.4.0-1029.32~18.04.1
- ubuntu•linux-raspi-realtime
all
- ubuntu•linux-raspi2
< 4.4.0-1146.156 | < 4.15.0-1079.84 | all
- ubuntu•linux-realtime
all
- ubuntu•linux-riscv
all
- ubuntu•linux-riscv-5.8
< 5.8.0-17.19~20.04.1
- ubuntu•linux-snapdragon
< 4.4.0-1150.160 | < 4.15.0-1096.105
Showing first 50 affected entries in server-rendered view.
References (22)
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=54ffccbf053b5b6ca4f6e45094b942fab92a25fc
- http://www.openwall.com/lists/oss-security/2020/12/10/1
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MZ7OAKAEFAXQRGBZK4LYUWINCD3D2XCL/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BOB25SU6XUL4TNP7KB63WNZSYTIYFDPP/
- https://www.debian.org/security/2021/dsa-4843
- https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html
- https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
- http://packetstormsecurity.com/files/160681/Linux-TIOCSPGRP-Broken-Locking.html
- https://security.netapp.com/advisory/ntap-20210122-0001/
- http://packetstormsecurity.com/files/164950/Kernel-Live-Patch-Security-Notice-LSN-0082-1.html
- https://ubuntu.com/security/CVE-2020-29661
- https://git.kernel.org/linus/54ffccbf053b5b6ca4f6e45094b942fab92a25fc
- https://bugs.chromium.org/p/project-zero/issues/detail?id=2125
- https://ubuntu.com/security/notices/USN-4748-1
- https://ubuntu.com/security/notices/USN-4749-1
- https://ubuntu.com/security/notices/USN-4750-1
- https://ubuntu.com/security/notices/USN-4751-1
- https://ubuntu.com/security/notices/USN-4752-1
- https://ubuntu.com/security/notices/USN-5130-1
- https://www.cve.org/CVERecord?id=CVE-2020-29661
- https://security-tracker.debian.org/tracker/CVE-2020-29661