The cookie feature in the packet action API implementation in net/sched/act_api.c in the Linux kernel 4.11.x through 4.11-rc7 mishandles the tb nlattr array, which allows local users to cause a denial of service (uninitialized memory access and refcount underflow, and system hang or crash) or possibly have unspecified other impact via "tc filter add" commands in certain contexts. NOTE: this does not affect stable kernels, such as 4.10.x, from kernel.org.
The MITRE CVE dictionary describes this issue as:
Find out more about CVE-2017-7979 from the MITRE CVE dictionary dictionary and NIST NVD.
NOTE: The following CVSS v3 metrics and score provided are preliminary and subject to review.
CVSS3 Base Score | 5.5 |
---|---|
CVSS3 Base Metrics | CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
Attack Vector | Local |
Attack Complexity | Low |
Privileges Required | Low |
User Interaction | None |
Scope | Unchanged |
Confidentiality | None |
Integrity Impact | None |
Availability Impact | High |
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 |