A use-after-free flaw was found in the way the Linux kernel's Datagram Congestion Control Protocol (DCCP) implementation freed SKB (socket buffer) resources for a DCCP_PKT_REQUEST packet when the IPV6_RECVPKTINFO option is set on the socket. A local, unprivileged user could use this flaw to alter the kernel memory, allowing them to escalate their privileges on the system.
Find out more about CVE-2017-6074 from the MITRE CVE dictionary dictionary and NIST NVD.
This issue affects Red Hat Enterprise Linux 5, 6, 7, and Red Hat Enterprise MRG 2 kernels.
As this issue is rated as Important, it has been scheduled to be fixed in a future version of Red Hat Enterprise Linux 5, 6, 7, and Red Hat Enterprise MRG 2 kernels.
| CVSS3 Base Score | 7.8 |
|---|---|
| CVSS3 Base Metrics | CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| Attack Vector | Local |
| Attack Complexity | Low |
| Privileges Required | Low |
| User Interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity Impact | High |
| Availability Impact | High |
| Platform | Errata | Release Date |
|---|---|---|
| Red Hat Enterprise Linux Extended Update Support 6.7 (kernel) | RHSA-2017:0316 | 2017-02-23 |
| Red Hat Enterprise Linux 5 (kernel) | RHSA-2017:0323 | 2017-02-24 |
| Red Hat Enterprise Linux Long Life (v. 5.6 server) (kernel) | RHSA-2017:0347 | 2017-02-28 |
| Red Hat Enterprise Linux Advanced Update Support 6.5 (kernel) | RHSA-2017:0366 | 2017-03-01 |
| Red Hat Enterprise Linux Advanced Update Support 6.4 (kernel) | RHSA-2017:0345 | 2017-02-28 |
| RHEV Hypervisor for RHEL-6 (rhev-hypervisor7) | RHSA-2017:1209 | 2017-05-09 |
| Red Hat Enterprise Linux Long Life (v. 5.9 server) (kernel) | RHSA-2017:0346 | 2017-02-28 |
| Red Hat Enterprise Linux for Real Time for NFV (v. 7) (kernel-rt) | RHSA-2017:0295 | 2017-02-22 |
| Red Hat Virtualization 4 Management Agent for RHEL 7 Hosts (rhev-hypervisor7) | RHSA-2017:1209 | 2017-05-09 |
| Red Hat MRG Grid for RHEL 6 Server v.2 (kernel-rt) | RHSA-2017:0932 | 2017-04-12 |
| Red Hat Enterprise Linux Extended Update Support 7.1 (kernel) | RHSA-2017:0403 | 2017-03-02 |
| Red Hat Enterprise Linux 6 (kernel) | RHSA-2017:0293 | 2017-02-22 |
| Red Hat Enterprise Linux Advanced Update Support 6.2 (kernel) | RHSA-2017:0365 | 2017-03-01 |
| Red Hat Enterprise Linux Extended Update Support 7.2 (kernel) | RHSA-2017:0501 | 2017-03-14 |
| Red Hat Enterprise Linux Advanced Update Support 6.6 (kernel) | RHSA-2017:0324 | 2017-02-24 |
| Red Hat Enterprise Linux Server TUS (v. 6.5) (kernel) | RHSA-2017:0366 | 2017-03-01 |
| Red Hat Enterprise Linux 7 (kernel) | RHSA-2017:0294 | 2017-02-22 |
| Red Hat Enterprise Linux Server TUS (v. 6.6) (kernel) | RHSA-2017:0324 | 2017-02-24 |
| Platform | Package | State |
|---|---|---|
| Red Hat Virtualization 4 | distribution | Affected |
| RHEV Manager 3 | distribution | Affected |
Recent versions of the SELinux policy can mitigate this flaw. The steps below will work with SELinux enabled or disabled.
As the DCCP module will be auto-loaded when required, its use can be disabled
by preventing the module from loading with the following instructions:
# echo "install dccp /bin/true" >> /etc/modprobe.d/disable-dccp.conf
The system will need to be restarted if the DCCP modules are loaded. In most circumstances, the DCCP kernel modules will be unable to be unloaded while any network interfaces are active and the protocol is in use.
If you need further assistance, see KCS article https://access.redhat.com/solutions/41278 or contact Red Hat Global Support Services.
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