Improper locking in Linux kernel - CVE-2020-29660
Published: October 4, 2021
Vulnerability identifier: #VU57039
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2020-29660
CWE-ID: CWE-667
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to gain access to sensitive information.
The vulnerability exists due to double-locking error in drivers/tty/tty_io.c and drivers/tty/tty_jobctrl.c. An authenticated local user can exploit this vulnerability to perform a read-after-free attack against TIOCGSID and gain access to sensitive information.
How to mitigate CVE-2020-29660
Install updates from vendor's website.
Sources
- http://www.openwall.com/lists/oss-security/2020/12/10/1
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c8bcd9c5be24fb9e6132e97da5a35e55a83e36b9
- https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html
- https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BOB25SU6XUL4TNP7KB63WNZSYTIYFDPP/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MZ7OAKAEFAXQRGBZK4LYUWINCD3D2XCL/
- https://security.netapp.com/advisory/ntap-20210122-0001/
- https://www.debian.org/security/2021/dsa-4843