SB2018021606 - Debian update for xen

Description

This security bulletin contains information about 4 secuirty vulnerabilities.

1) Memory corruption (CVE-ID: CVE-2017-17563)

The vulnerability allows an adjacent attacker to gain elevated privileges or cause a denial of service (DoS) condition on a targeted host system.

The weakness exists due to insufficient reference count overflow checking. An adjacent attacker can use a mask that is larger than the reference count that is set on a targeted system, trigger memory corruption and cause the hypervisor to crash or gain elevated privileges.

2) Denial of service (CVE-ID: CVE-2017-17564)

The vulnerability allows an adjacent attacker to cause DoS condition or gain elevated privileges.

The weakness exists due to improper error handling for reference counts. A remote attacker can trigger memory corruption, cause the hypervisor to crash or gain elevated privileges on the target system.

3) Denial of service (CVE-ID: CVE-2017-17565)

The vulnerability allows an adjacent attacker to cause DoS condition on the target system.

The weakness exists due to improper assertion related to machine-to-physical (M2P) translation table entries. A remote attacker can cause the system to crash.

4) Denial of service (CVE-ID: CVE-2017-17566)

The vulnerability allows an adjacent attacker to cause DoS condition on the target system.

The weakness exists due to improper auxiliary page mapping. A remote attacker can cause the system to crash.

Remediation

Install update from vendor's website.

References

• https://xenbits.xen.org/xsa/advisory-249.html
• https://xenbits.xen.org/xsa/advisory-250.html
• https://xenbits.xen.org/xsa/advisory-251.html
• https://xenbits.xen.org/xsa/advisory-248.html