SB2023092955 - SUSE update for xen

Description

This security bulletin contains information about 4 secuirty vulnerabilities.

1) Information exposure through microarchitectural state after transient execution (CVE-ID: CVE-2022-40982)

The vulnerability allows a malicious guest to escalate privileges on the system.

The vulnerability exists due to the way data is shared between threads whereby the AVX GATHER instructions on Intel processors can forward the content of stale vector registers to dependent instructions. A malicious guest can infer data from different contexts on the same core and execute arbitrary code with elevated privileges.

2) Division by zero (CVE-ID: CVE-2023-20588)

The vulnerability allows a local user to gain access to sensitive information.

The vulnerability exists due to a divide by zero error that can return speculative data. A local user can gain access to potentially sensitive information.

3) Use-after-free (CVE-ID: CVE-2023-20593)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a use-after-free error in AMD Zen2 processors. A local user can trigger a use-after-free error and execute arbitrary code on the system.

Note, the vulnerability was dubbed Zenbleed.

4) Resource management error (CVE-ID: CVE-2023-34322)

The vulnerability allows a malicious guest to escalate privileges on the system.

The vulnerability exists due to improper management of internal resources when running PV guests in shadow paging mode. A malicious guest can run a specially crafted application on the system that causes shortage of memory in the associated with the domain shadow pool and forces Xen to tear down page tables. This can result in memory leak, denial of service or privilege escalation.

The vulnerability can be exploited by 64-bit PV guests on x86 systems.

Remediation

Install update from vendor's website.

References

• https://www.suse.com/support/update/announcement/2023/suse-su-20233894-1/