The adjust_branches function in kernel/bpf/verifier.c in the Linux kernel before 4.5 does not consider the delta in the backward-jump case, which allows local users to obtain sensitive information from kernel memory by creating a packet filter and then loading crafted BPF instructions.
The MITRE CVE dictionary describes this issue as:
Find out more about CVE-2016-2383 from the MITRE CVE dictionary dictionary and NIST NVD.
This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5, 6, 7 and MRG-2, as the code with the flaw is not present in the products listed.
NOTE: The following CVSS v2 metrics and score provided are preliminary and subject to review.
| Base Score | 1.7 |
|---|---|
| Base Metrics | AV:L/AC:L/Au:S/C:P/I:N/A:N |
| Access Vector | Local |
| Access Complexity | Low |
| Authentication | Single |
| Confidentiality Impact | Partial |
| Integrity Impact | None |
| Availability Impact | None |
Find out more about Red Hat support for the Common Vulnerability Scoring System (CVSS).
| Platform | Package | State |
|---|---|---|
| Red Hat Enterprise MRG 2 | realtime-kernel | Not affected |
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected |
| Red Hat Enterprise Linux 7 | kernel | Not affected |
| Red Hat Enterprise Linux 6 | kernel | Not affected |
| Red Hat Enterprise Linux 5 | kernel | Not affected |
Vulmon