Buffer overflow in Linux Kernel

CVE-2019-3701

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.

Vulnerability class: Buffer Overflow

EPSS: 0.007 (49.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

  • cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (VDB Entry, Third Party Advisory, vdb-entry, x_refsource_BID)
  • cve@mitre.org (Exploit, Patch, Third Party Advisory, x_refsource_MISC, Issue Tracking)
  • cve@mitre.org (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
  • cve@mitre.org (mailing-list, x_refsource_MLIST, Mailing List, Third Party Advisory)
  • cve@mitre.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (x_refsource_UBUNTU, vendor-advisory, Third Party Advisory)
  • cve@mitre.org (x_refsource_CONFIRM, Third Party Advisory)
  • cve@mitre.org (Patch, Mailing List, Third Party Advisory, x_refsource_MISC)
  • cve@mitre.org (Patch, Mailing List, x_refsource_MISC, Vendor Advisory)

Frequently asked questions

What is CVE-2019-3701?
CVE-2019-3701 is a medium-severity vulnerability in Linux Kernel, classified under Out-of-bounds Write. CVSS score: 4.4/10. Published 2019-01-03.
How severe is CVE-2019-3701?
Medium severity. CVSS v3 base score is 4.4 out of 10.