Denial of service in Linux Kernel
| Risk | Low |
| Patch available | YES |
| Number of vulnerabilities | 5 |
| CVE-ID | CVE-2017-1000405 CVE-2017-15951 CVE-2017-15306 CVE-2017-15299 CVE-2017-16939 |
| CWE-ID | CWE-362 CWE-476 CWE-416 |
| Exploitation vector | Local |
| Public exploit |
Public exploit code for vulnerability #1 is available. Public exploit code for vulnerability #5 is available. |
| Vulnerable software Subscribe |
Linux kernel Operating systems & Components / Operating system |
| Vendor | Linux Foundation |
Security Bulletin
This security bulletin contains information about 5 vulnerabilities.
1) Race condition
EUVDB-ID: #VU9520
Risk: Low
CVSSv3.1: 5.9 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:P/RL:O/RC:C]
CVE-ID: CVE-2017-1000405
Exploit availability: Yes
DescriptionThe vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to a race condition within touch_pmd() function in mmhugemem.c file when handling THPs. A local user can read read-only huge pages using the get_user_pages() function and overwrite arbitrary huge pages and files mapped via THP.
Successful exploitation of the vulnerability may allow an attacker to perform a denial of service (DoS) attack.
This vulnerability is a result of patch against a another privilege escalation vulnerability in Linux kernel known as Dirty Cow (CVE-2016-5195).
Install a patch from vendor's repository:
https://github.com/torvalds/linux/commit/a8f97366452ed491d13cf1e44241bc0b5740b1f0
Linux kernel: 2.6.38 - 4.14
External linkshttp://github.com/torvalds/linux/commit/a8f97366452ed491d13cf1e44241bc0b5740b1f0
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.
2) Race condition
EUVDB-ID: #VU9604
Risk: Low
CVSSv3.1: 5.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2017-15951
Exploit availability: No
DescriptionThe vulnerability allows a local attacker to cause DoS condition on the target system.
The weakness exists due to the KEYS subsystem does not correctly synchronize the actions of updating versus finding a key in the "negative" state. A local attacker can make a specially crafted system calls, trigger race condition and cause the service to crash.
Successful exploitation of the vulnerability results in denial of service.
Update to version 4.13.10.
Linux kernel: 4.4.11 - 4.13.9
External linksQ & 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.
3) Null pointer dereference
EUVDB-ID: #VU9603
Risk: Low
CVSSv3.1: 5.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2017-15306
CWE-ID:
CWE-476 - NULL Pointer Dereference
Exploit availability: No
DescriptionThe vulnerability allows a local attacker to cause DoS condition on the target system.
The weakness exists due to NULL pointer dereference in the kvm_vm_ioctl_check_extension function in arch/powerpc/kvm/powerpc.c in the Linux kernel. A local attacker can make a KVM_CHECK_EXTENSION KVM_CAP_PPC_HTM ioctl call to /dev/kvm and cause the service to crash.
Successful exploitation of the vulnerability results in denial of service.
Update to version 4.13.11.
Linux kernel: 4.4.11 - 4.13.10
External linksQ & 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.
4) Null pointer dereference
EUVDB-ID: #VU9602
Risk: Low
CVSSv3.1: 5.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]
CVE-ID: CVE-2017-15299
CWE-ID:
CWE-476 - NULL Pointer Dereference
Exploit availability: No
DescriptionThe vulnerability allows a local attacker to cause DoS condition on the target system.
The weakness exists due to the KEYS subsystem mishandles use of add_key for a key that already exists but is uninstantiated. A local attacker can supply specially crafted keys, trigger null pointer dereference and cause the service to crash.
Successful exploitation of the vulnerability results in denial of service.
Update to version 4.13.7.
Linux kernel: 4.4.11 - 4.13.6
External linkshttp://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1499828.html
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) Use-after-free error
EUVDB-ID: #VU9601
Risk: Low
CVSSv3.1: 5.9 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H/E:P/RL:O/RC:C]
CVE-ID: CVE-2017-16939
CWE-ID:
CWE-416 - Use After Free
Exploit availability: Yes
DescriptionThe vulnerability allows a local attacker to cause DoS condition on the target system.
The weakness exists in the XFRM dump policy implementation in net/xfrm/xfrm_user.c in the Linux kernel due to use-after-free error. A local attacker can make a specially crafted SO_RCVBUF setsockopt system call in conjunction with XFRM_MSG_GETPOLICY Netlink messages, trigger memory corruption and cause the service to crash.
Successful exploitation of the vulnerability results in denial of service.
Update to version 4.13.11.
Linux kernel: 4.4.11 - 4.13.10
External linksQ & 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.
