CVE Tools

CVE-2026-79609

x86: XPTI may break on huge-memory systems

No known exploitation. EPSS puts it in the 1st percentile. Only a workaround so far.

Check it yourself

OpenVAS · 8 checks

e.g. OID 1.3.6.1.4.1.25623.1.1.1.1.2026.6571

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Published Updated Sources: CVE.org, NVD

What to do

No fixed build is published yet. The vendor describes a workaround.

What it is

From the CVE record

XPTI (Xen Page Table Isolation) was introduced to mitigate Meltdown (CVE-2017-5754, one aspect of XSA-254). This involves copying 64-bit PV guest page table entries from guest-chosen root page tables to the Xen- chosen one which is in actual use by hardware. To read the guest root page table, the directmap is used. PV guests, however, have a directmap which may not cover all memory; in particular this is the case if any memory extends beyond the 5 TiB (CONFIG_BIGMEM=y: 3.5 TiB) address boundary.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS1st
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.1% chance of exploitation activity in the next 30 days, which ranks it in the 1st percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

10 events over 9 days, from the signal feeds we watch.

  1. OpenVAS check added
  2. Workaround availablerecord updated
  3. Workaround availablerecord updated
  4. Workaround availableworkaround available, published, weakness classified, record updated

Affected products

Technical detail

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Scored 8.8 by NVD.

How it is reached

  • Attack Vector LocalRequires local access to the vulnerable system (e.g. local login, malicious file)
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required LowRequires basic user-level privileges
  • User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

  • Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)

Impact if exploited

  • Confidentiality HighTotal information disclosure — all data in the component is compromised
  • Integrity HighTotal loss of integrity — attacker can modify any data in the component
  • Availability HighTotal denial of service — the component is completely unavailable

Weaknesses

Sources

Watch the software you run.

My Stack ranks new CVEs for your products by real-world exploitation, so the next serious one reaches you without reading every advisory.

We'll flag the next CVE, public exploit or patch for Xen, not every advisory.