Red Hat update for Linux Kernel

1) Memory corruption

EUVDB-ID: #VU7131

Risk: Medium

CVSSv3.1: 8.2 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:F/RL:O/RC:C]

CVE-ID: CVE-2017-1000364

CWE-ID: CWE-119 - Memory corruption

Exploit availability: Yes

Description

The vulnerability allows a local attacker to gain elevated privileges on the target system.

The vulnerability exists due to memory management errors in implementation of various functions under multiple operating systems. A local or remote attacker can trigger the affected application to process specially crafted data, trigger memory corruption and execute arbitrary code on the target system. The vulnerability is dubbed by Qualys researchers as “Stack Clash”.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

kernel-rt (Red Hat package): 3.10.0-229.1.2.rt56.141.2.el7_1 - 3.10.0-514.21.1.rt56.438.el7

Red Hat Enterprise Linux for Real Time: 7

Red Hat Enterprise Linux for Real Time for NFV: 7

:

External links

http://access.redhat.com/errata/RHSA-2017:1616

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.

2) Denial of service

EUVDB-ID: #VU5183

Risk: Low

CVSSv3.1: 5.9 [CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-2583

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows an adjacent attacker to cause DoS condition.

The weakness exists due to improper emulation of "MOV SS, NULL selector" instruction by the load_segment_descriptor implementation in arch/x86/kvm/emulate.c in the Linux kernel. A quest OS user can use a specially crafted and cause the system to crash.

Successful exploitation of the vulnerability results in denial of service.

Mitigation

Install update from vendor's website.

Vulnerable software versions

kernel-rt (Red Hat package): 3.10.0-229.1.2.rt56.141.2.el7_1 - 3.10.0-514.21.1.rt56.438.el7

Red Hat Enterprise Linux for Real Time: 7

Red Hat Enterprise Linux for Real Time for NFV: 7

:

External links

http://access.redhat.com/errata/RHSA-2017:1616

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Infinite loop

EUVDB-ID: #VU6651

Risk: Medium

CVSSv3.1: 7.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-6214

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform denial of service (DoS) attack.

The vulnerability exists due to an error in tcp_splice_read() function in net/ipv4/tcp.c in Linux kernel before 4.9.11. A remote attacker can send a specially crafted TCP packet with the URG flag and trigger infinite loop.

Successful exploitation of the vulnerability may allow an attacker to perform denial of service (DoS) attack.

Mitigation

Install update from vendor's website.

Vulnerable software versions

kernel-rt (Red Hat package): 3.10.0-229.1.2.rt56.141.2.el7_1 - 3.10.0-514.21.1.rt56.438.el7

Red Hat Enterprise Linux for Real Time: 7

Red Hat Enterprise Linux for Real Time for NFV: 7

:

External links

http://access.redhat.com/errata/RHSA-2017:1616

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

4) Heap-based buffer overflow

EUVDB-ID: #VU6612

Risk: Medium

CVSSv3.1: 7.8 [CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-7477

CWE-ID: CWE-122 - Heap-based Buffer Overflow

Exploit availability: No

Description

The vulnerability allows a remote attacker on the local network execute arbitrary code on the target system.

The weakness exists due to heap-based buffer overflow in the skb_to_sgvec() function in the MACsec driver. A remote attacker can use a MAX_SKB_FRAGS+1 size in conjunction with the NETIF_F_FRAGLIST feature, trigger memory corruption and execute arbitrary code with root privileges.

Successful exploitation of the vulnerability results in arbitrary code execution.

Mitigation

Install update from vendor's website.

Vulnerable software versions

kernel-rt (Red Hat package): 3.10.0-229.1.2.rt56.141.2.el7_1 - 3.10.0-514.21.1.rt56.438.el7

Red Hat Enterprise Linux for Real Time: 7

Red Hat Enterprise Linux for Real Time for NFV: 7

:

External links

http://access.redhat.com/errata/RHSA-2017:1616

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

5) Denial of service

EUVDB-ID: #VU6659

Risk: Medium

CVSSv3.1: 7.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-7645

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to cause DoS condition on the target system.

The weakness exists due to a flaw in the NFSv2/NFSv3 server in the nfsd subsystem. A remote attacker can use a long RPC reply related to net/sunrpc/svc.c, fs/nfsd/nfs3xdr.c, and fs/nfsd/nfsxdr.c. and cause the system to crash.

Successful exploitation of the vulnerability results in denial of service.

Mitigation

Install update from vendor's website.

Vulnerable software versions

kernel-rt (Red Hat package): 3.10.0-229.1.2.rt56.141.2.el7_1 - 3.10.0-514.21.1.rt56.438.el7

Red Hat Enterprise Linux for Real Time: 7

Red Hat Enterprise Linux for Real Time for NFV: 7

:

External links

http://access.redhat.com/errata/RHSA-2017:1616

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

6) Security restrictions bypass

EUVDB-ID: #VU7238

Risk: Low

CVSSv3.1: 6.4 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-7895

CWE-ID: CWE-119 - Memory corruption

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass security restrictions on the target system.

The weakness exists due to boundary error when handling a user-supplied input. A remote attacker can send a specially crafted request, trigger pointer-arithmetic errors or possibly have unspecified other impact related to fs/nfsd/nfs3xdr.c and fs/nfsd/nfsxdr.c.

Successful exploitation of the vulnerability results in access to the system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

kernel-rt (Red Hat package): 3.10.0-229.1.2.rt56.141.2.el7_1 - 3.10.0-514.21.1.rt56.438.el7

Red Hat Enterprise Linux for Real Time: 7

Red Hat Enterprise Linux for Real Time for NFV: 7

:

External links

http://access.redhat.com/errata/RHSA-2017:1616

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.