Bug 642312 (CVE-2017-16996)

Summary:	kernel: memory corruption caused by BPF verifier bugs can allow for arbitrary code execution (CVE-2017-16996)
Product:	Gentoo Security	Reporter:	Thomas Deutschmann (RETIRED) <whissi>
Component:	Kernel	Assignee:	Gentoo Kernel Security <security-kernel>
Status:	RESOLVED FIXED
Severity:	critical	CC:	kernel, kfm
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
URL:	http://seclists.org/oss-sec/2017/q4/429
Whiteboard:
Package list:		Runtime testing required:	---

Description Thomas Deutschmann (RETIRED) gentoo-dev

2017-12-26 12:59:28 UTC

Linux kernel built with the eBPF bpf(2) system call(CONFIG_BPF_SYSCALL) support
is vulnerable to an arbitrary memory r/w access issue. It could occur if a user supplied a malicious BPF program which results calculations error in eBPF verifier module.

An unprivileged user could use this flaw to escalate their privileges on a system.

Upstream patch
--------------
  -> https://git.kernel.org/linus/3db9128fcf02dcaafa3860a69a8a55d5529b6e30

References:
-----------
  -> http://seclists.org/oss-sec/2017/q4/429
  -> http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2017-16996
  -> http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-16996
  -> https://bugs.chromium.org/p/project-zero/issues/detail?id=1454

Mitigation:
-----------
  # echo 1 > /proc/sys/kernel/unprivileged_bpf_disabled

Comment 1 John Helmert III archtester

2022-03-26 01:51:46 UTC

Bug introduced in 4.14, patch in 4.14.9. ALl done!