Red Hat update for kernel

Published: 2019-12-03 | Updated: 2019-12-03
Severity Medium
Patch available YES
Number of vulnerabilities 6
CVE ID CVE-2019-11811
CVE-2019-7221
CVE-2019-5489
CVE-2017-18208
CVE-2019-3900
CVE-2017-10661
CWE ID CWE-416
CWE-200
CWE-835
CWE-362
Exploitation vector Local network
Public exploit Public exploit code for vulnerability #2 is available.
Public exploit code for vulnerability #3 is available.
Vulnerable software Red Hat Enterprise Linux Server Subscribe
Red Hat Enterprise Linux for Power
Red Hat Enterprise Linux for x86_64
Vendor Red Hat Inc.

Security Advisory

1) Use-after-free

Severity: Low

CVSSv3: 7.7 [CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C] [PCI]

CVE-ID: CVE-2019-11811

CWE-ID: CWE-416 - Use After Free

Description

The vulnerability allows a local usre to elevate privileges on the system.

The vulnerability exists due to a use-after-free error when trying to read data from /proc/ioports after the ipmi_si module is removed (related to drivers/char/ipmi/ipmi_si_intf.c, drivers/char/ipmi/ipmi_si_mem_io.c, and drivers/char/ipmi/ipmi_si_port_io.c). A local user can exploit this issue to elevate privileges on the system.


Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux Server: 7.4

Red Hat Enterprise Linux for Power: 7.4

Red Hat Enterprise Linux for x86_64: 7.4

CPE External links

https://access.redhat.com/errata/RHSA-2019:4058

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.

2) Use-after-free

Severity: Medium

CVSSv3: 8.6 [CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C] [PCI]

CVE-ID: CVE-2019-7221

CWE-ID: CWE-416 - Use After Free

Description

The vulnerability allows an adjacent attacker to cause DoS condition or execute arbitrary code.

The weakness exists due to exists due to use-after-free error when using emulated vmx preemption timer. An adjacent attacker can cause the service to crash or execute arbitrary code with elevated privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux Server: 7.4

Red Hat Enterprise Linux for Power: 7.4

Red Hat Enterprise Linux for x86_64: 7.4

CPE External links

https://access.redhat.com/errata/RHSA-2019:4058

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.

3) Information disclosure

Severity: Low

CVSSv3: 5.2 [CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N/E:P/RL:U/RC:C] [PCI]

CVE-ID: CVE-2019-5489

CWE-ID: CWE-200 - Information Exposure

Description

The vulnerability allows a local attacker to gain access to potentially sensitive information.

The vulnerability exists due to a flaw in the mincore() implementation in mm/mincore.c. A local attacker can observe page cache access patterns of other processes on the same system and sniff secret information.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux Server: 7.4

Red Hat Enterprise Linux for Power: 7.4

Red Hat Enterprise Linux for x86_64: 7.4

CPE External links

https://access.redhat.com/errata/RHSA-2019:4058

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, proof of concept for this vulnerability is available.

4) Infinite loop

Severity: Low

CVSSv3: 3.5 [CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-18208

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

Description

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

The weakness exists in the madvise_willneed function due to infinite loop. A local attacker can trigger use of MADVISE_WILLNEED for a DAX mapping and cause the service to crash.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux Server: 7.4

Red Hat Enterprise Linux for Power: 7.4

Red Hat Enterprise Linux for x86_64: 7.4

CPE External links

https://access.redhat.com/errata/RHSA-2019:4058

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.

5) Infinite loop

Severity: Low

CVSSv3: 3.1 [CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-3900

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

Description

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

The vulnerability exists due to infinite loop in vhost_net kernel module when processing incoming packets in handle_rx(). A remote attacker with access to guest operating system can stall the vhost_net kernel thread and cause denial of service conditions.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux Server: 7.4

Red Hat Enterprise Linux for Power: 7.4

Red Hat Enterprise Linux for x86_64: 7.4

CPE External links

https://access.redhat.com/errata/RHSA-2019:4058

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.

6) Race condition

Severity: Low

CVSSv3: 7.7 [CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C] [PCI]

CVE-ID: CVE-2017-10661

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Description

The vulnerability allows a local attacker to gain elevated privileges or cause DoS condition on the target system.

The weakness exists due to race condition in fs/timerfd.c in the Linux kernel. A local attacker can use simultaneous file-descriptor operations, leverage improper might_cancel queueing, trigger list corruption or use-after-free and cause the service to crash or execute arbitrary code with root privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux Server: 7.4

Red Hat Enterprise Linux for Power: 7.4

Red Hat Enterprise Linux for x86_64: 7.4

CPE External links

https://access.redhat.com/errata/RHSA-2019:4058

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.