UBUNTU-CVE-2019-13272
In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to create a ptrace relationship, which allows local users to obtain root access by leveraging certain scenarios with a parent-child process relationship, where a parent drops privileges and calls execve (potentially allowing control by an attacker). One contributing factor is an object lifetime issue (which can also cause a panic). Another contributing factor is incorrect marking of a ptrace relationship as privileged, which is exploitable through (for example) Polkit's pkexec helper with PTRACE_TRACEME. NOTE: SELinux deny_ptrace might be a usable workaround in some environments.
02 / AFFECTED SOFTWARE
Affected packages
65 explicit affected versions
23 explicit affected versions
3 explicit affected versions
29 explicit affected versions
10 explicit affected versions
1 explicit affected versions
33 explicit affected versions
1 explicit affected versions
1 explicit affected versions
12 explicit affected versions
1 explicit affected versions
33 explicit affected versions
10 explicit affected versions
10 explicit affected versions
34 explicit affected versions
9 explicit affected versions
27 explicit affected versions
1 explicit affected versions
6 explicit affected versions
23 explicit affected versions
11 explicit affected versions
67 explicit affected versions
29 explicit affected versions
34 explicit affected versions
95 explicit affected versions
51 explicit affected versions
41 explicit affected versions
1 explicit affected versions
1 explicit affected versions
54 explicit affected versions
12 explicit affected versions
30 explicit affected versions
26 explicit affected versions
26 explicit affected versions
75 explicit affected versions
54 explicit affected versions
9 explicit affected versions
21 explicit affected versions
12 explicit affected versions
1 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to create a ptrace relationship, which allows local users to obtain root access by leveraging certain scenarios with a parent-child process relationship, where a parent drops privileges and calls execve (potentially allowing control by an attacker). One contributing factor is an object lifetime issue (which can also cause a panic). Another contributing factor is incorrect marking of a ptrace relationship as privileged, which is exploitable through (for example) Polkit's pkexec helper with PTRACE_TRACEME. NOTE: SELinux deny_ptrace might be a usable workaround in some environments.
05 / REFERENCES
Further evidence
- http://packetstormsecurity.com/files/153663/Linux-PTRACE_TRACEME-Broken-Permission-Object-Lifetime-Handling.html
- https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6994eefb0053799d2e07cd140df6c2ea106c41ee
- https://ubuntu.com/security/CVE-2019-13272
- https://ubuntu.com/security/notices/USN-4093-1
- https://ubuntu.com/security/notices/USN-4094-1
- https://ubuntu.com/security/notices/USN-4095-1
- https://ubuntu.com/security/notices/USN-4117-1
- https://ubuntu.com/security/notices/USN-4118-1
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- https://www.cve.org/CVERecord?id=CVE-2019-13272