CVE-2016-4913
kernel: Information leak when handling NM entries containing NUL
Severity
LowRed Hat Product Security
CVSS 2.0
Review impact separately from score.
Published · May 5, 2016
Updated · June 28, 2026
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.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 2.0 · 2.1AV:L/AC:L/Au:N/C:P/I:N/A:N
CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor