CVE-2016-4913
Description
A vulnerability was found in the Linux kernel. Payloads of NM entries are not supposed to contain NUL. When such entry is processed, only the part prior to the first NUL goes into the concatenation (i.e. the directory entry name being encoded by a bunch of NM entries). The process stops when the amount collected so far + the claimed amount in the current NM entry exceed 254. However, the value returned as the total length is the sum of claimed sizes, not the actual amount collected. And that's what will be passed to readdir() callback as the name length - 8Kb __copy_to_user() from a buffer allocated by __get_free_page().
Statement
This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 5, 6 and MRG-2. This has been rated as having Low security impact and is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.
This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 7. Future Linux kernel updates for the respective releases might address this issue.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v2 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 2.1 | 7.2 | N/A |
| Attack Vector | Local | Local | N/A |
| Access Complexity | Low | Low | N/A |
| Authentication | None | None | N/A |
| Confidentiality Impact | Partial | Complete | N/A |
| Integrity Impact | None | Complete | N/A |
| Availability Impact | None | Complete | N/A |
Vector
Red Hat: AV:L/AC:L/Au:N/C:P/I:N/A:N
NVD: AV:L/AC:L/Au:N/C:C/I:C/A:C
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data
Frequently Asked Questions
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