CVE-2019-3701: canonical ubuntu_linux Out-of-bounds Write

Vulnerability summary

CVE-2019-3701 is a medium (CVSS 4.9) Out-of-bounds Write vulnerability in canonical ubuntu_linux. EPSS estimates a 0.70% chance of exploitation in the next 30 days, higher than 53.1% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 03-01-2019
   PublishedVulnerability first disclosed.
2. 04-08-2024
   Last modifiedVulnerability information updated.

Description

An issue was discovered in can_can_gw_rcv in net/can/gw.c in the Linux kernel through 4.19.13. The CAN frame modification rules allow bitwise logical operations that can be also applied to the can_dlc field. The privileged user "root" with CAP_NET_ADMIN can create a CAN frame modification rule that makes the data length code a higher value than the available CAN frame data size. In combination with a configured checksum calculation where the result is stored relatively to the end of the data (e.g. cgw_csum_xor_rel) the tail of the skb (e.g. frag_list pointer in skb_shared_info) can be rewritten which finally can cause a system crash. Because of a missing check, the CAN drivers may write arbitrary content beyond the data registers in the CAN controller's I/O memory when processing can-gw manipulated outgoing frames.

• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.