CVE Number – CVE-2018-14616
A vulnerability in the fscrypt_do_page_crypto() function of the Linux Kernel could allow a local attacker to cause a denial of service (DoS) condition on a targeted system.
The vulnerability occurs when the fscrypt_do_page_crypto() function, as defined in the fs/crypto/crypto.c source code file of the affected software, operates on a file in a corrupted Flash-Friendly File System (F2FS) image. An attacker could exploit this vulnerability by mounting a malicious F2FS image on a targeted system and operating on a file in the image, triggering a NULL pointer dereference condition. A successful exploit could cause the affected software to crash, resulting in a DoS condition.
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.
To exploit this vulnerability, the attacker must have user-level access to the targeted system. This access requirement may reduce the likelihood of a successful exploit.
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.
Kernel.org has released a bug report at the following link: Bug 200465
Kernel.org has a patch at the following link: f2fs: fix to do sanity check with block address in main area v2
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.