Linux Kernel coredump Implementation Local Information Disclosure Vulnerability [CVE-2019-11599]
CVE Number – CVE-2019-11599
A vulnerability in the Linux Kernel could allow a local attacker to access sensitive information on a targeted system.The vulnerability is related to the fs/userfaultfd.c, mm/mmap.c, fs/proc/task_mmu.c, and drivers/infiniband/core/uverbs_main.c source code files of the affected software, and exists because the coredump implementation fails to prevent changes to virtual memory area (VMA) layouts or VMA flags while it runs. An attacker could exploit this vulnerability by accessing the system and making malicious mmget_not_zero or get_task_mm calls. A successful exploit could cause a race condition and allow the attacker to access sensitive information, which could be used to conduct further attacks.Proof-of-concept (PoC) code that demonstrates an exploit of this vulnerability is publicly available.Kernel.org has confirmed the vulnerability and released software updates.
Analysis
- To exploit this vulnerability, the attacker must have user-level access to the targeted system. This access requirement could reduce the likelihood of a successful exploit.
Safeguards
- Administrators are advised to apply the appropriate updates.Administrators are advised to allow only trusted users to access local systems.Administrators are advised to allow only privileged users to access administration or management systems.Administrators are advised to monitor critical systems.
Vendor Announcements
- Kernel.org has released a git commit at the following link: commit 04f5866e41fb70690e28397487d8bd8eea7d712a
Fixed Software
- Kernel.org has released software updates at the following link: coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping
Duncan is a technology professional with over 20 years experience of working in various IT roles. He has a interest in cyber security, and has a wide range of other skills in radio, electronics and telecommunications.