CVE-2020-29661
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.
02 / AFFECTED SOFTWARE
Affected packages
1 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
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.
In tiocspgrp of tty_jobctrl.c, there is a possible use after free due to a race condition. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.
05 / REFERENCES
Further evidence
- http://packetstormsecurity.com/files/160681/Linux-TIOCSPGRP-Broken-Locking.html
- http://packetstormsecurity.com/files/164950/Kernel-Live-Patch-Security-Notice-LSN-0082-1.html
- 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=54ffccbf053b5b6ca4f6e45094b942fab92a25fc
- 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%40lists.fedoraproject.org/message/BOB25SU6XUL4TNP7KB63WNZSYTIYFDPP/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MZ7OAKAEFAXQRGBZK4LYUWINCD3D2XCL/
- https://security.netapp.com/advisory/ntap-20210122-0001/
- https://www.debian.org/security/2021/dsa-4843
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://android.googlesource.com/kernel/common/+/54ffccbf053b5b6ca4f6e45094b942fab92a25fc
- https://source.android.com/security/bulletin/2021-05-01