Skip to main content

Over 150 LLM Providers · Over 5,300 Models The most extensible AI-powered pentesting platform. Open source. Star on GitHub

CVE-2019-18423

8.8 · HIGH
Published Oct 31, 2019 xen CWE-193

Overview

CVE-2019-18423 is a high-severity vulnerability affecting xen xen. It was published on October 31, 2019 and has a CVSS 3.1 base score of 8.8 (HIGH).

This vulnerability has a CVSS 3.1 base score of 8.8, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.

Technical Description

An issue was discovered in Xen through 4.12.x allowing ARM guest OS users to cause a denial of service via a XENMEM_add_to_physmap hypercall. p2m->max_mapped_gfn is used by the functions p2m_resolve_translation_fault() and p2m_get_entry() to sanity check guest physical frame. The rest of the code in the two functions will assume that there is a valid root table and check that with BUG_ON(). The function p2m_get_root_pointer() will ignore the unused top bits of a guest physical frame. This means that the function p2m_set_entry() will alias the frame. However, p2m->max_mapped_gfn will be updated using the original frame. It would be possible to set p2m->max_mapped_gfn high enough to cover a frame that would lead p2m_get_root_pointer() to return NULL in p2m_get_entry() and p2m_resolve_translation_fault(). Additionally, the sanity check on p2m->max_mapped_gfn is off-by-one allowing "highest mapped + 1" to be considered valid. However, p2m_get_root_pointer() will return NULL. The problem co

Remediation

Check the references section for vendor advisories and patches from xen. Update xen to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

Affected Products

Vendor Product Versions Status
xen xen 4.8 Affected

Frequently Asked Questions

What is CVE-2019-18423?

CVE-2019-18423 is a high-severity vulnerability affecting xen xen. It was published on October 31, 2019 and has a CVSS 3.1 base score of 8.8 (HIGH).

How severe is CVE-2019-18423?

This vulnerability has a CVSS 3.1 base score of 8.8, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.

How do I fix or remediate CVE-2019-18423?

Check the references section for vendor advisories and patches from xen. Update xen to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

How can CyberStrike help with CVE-2019-18423?

CyberStrike's AI-powered security agents can automatically detect CVE-2019-18423 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.