CVE-2026-43045

Description

In the Linux kernel, the following vulnerability has been resolved: mshv: Fix error handling in mshv_region_pin The current error handling has two issues: First, pin_user_pages_fast() can return a short pin count (less than requested but greater than zero) when it cannot pin all requested pages. This is treated as success, leading to partially pinned regions being used, which causes memory corruption. Second, when an error occurs mid-loop, already pinned pages from the current batch are not properly accounted for before calling mshv_region_invalidate_pages(), causing a page reference leak. Treat short pins as errors and fix partial batch accounting before cleanup.

CVSS v3.1 Score

5.5

MEDIUM

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

EPSS — Exploit Prediction

0.0002

Probability of exploitation

0.04%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Affected Products

Vendor	Product	Versions
linux	linux_kernel	6.15 — 6.19.12
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/a7d149152bc5a9119854331c57be35ad31fdf5cc https://git.kernel.org/stable/c/c0e296f257671ba10249630fe58026f29e4804d9

Frequently Asked Questions

What is CVE-2026-43045? +

In the Linux kernel, the following vulnerability has been resolved: mshv: Fix error handling in mshv_region_pin The current error handling has two issues: First, pin_user_pages_fast() can return a short pin count (less than requested but greater than zero) when it cannot pin all requested pages. This is treated as success, leading to partially pinned regions being used, which causes memory corruption. Second, when an error occurs mid-loop, already pinned pages from the current batch are not properly accounted for before calling mshv_region_invalidate_pages(), causing a page reference leak. Treat short pins as errors and fix partial batch accounting before cleanup. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2026-43045? +

CVE-2026-43045 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0002, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-43045? +

CVE-2026-43045 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-43045? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-9588 10.0

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') vulnerability in Iron Mountain Archiving Services Inc. …

CVE-2025-57870 10.0

A SQL Injection vulnerability exists in Esri ArcGIS Server versions 11.3, 11.4 and 11.5 on Windows, Linux and Kubernetes. This …

CVE-2025-34028 10.0

The Commvault Command Center Innovation Release allows an unauthenticated actor to upload ZIP files that represent install packages that, when …

CVE-2024-25693 9.9

There is a path traversal in Esri Portal for ArcGIS versions <= 11.2. Successful exploitation may allow a remote, authenticated …

CVE-2026-31657 9.8

In the Linux kernel, the following vulnerability has been resolved: batman-adv: hold claim backbone gateways by reference batadv_bla_add_claim() can replace …

CVE-2026-31649 9.8

In the Linux kernel, the following vulnerability has been resolved: net: stmmac: fix integer underflow in chain mode The jumbo_frm() …