Critical severity9.3NVD Advisory· Published Jul 19, 2026· Updated Jul 27, 2026
CVE-2026-63940
CVE-2026-63940
Description
In the Linux kernel, the following vulnerability has been resolved:
KVM: SEV: Ignore Port I/O requests of length '0'
Explicitly ignore Port I/O requests of length '0' (or count '0'), so that setting up the software scratch area (and other code) doesn't have to worry about underflowing the length, and to allow for WARNing on trying to configure the scratch area with len==0.
Affected products
15- osv-coords14 versionspkg:linux/kernelpkg:rpm/opensuse/dtb-aarch64&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-64kb&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-azure&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-default&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-default-base&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-docs&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-kvmsmall&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-obs-build&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-obs-qa&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-rt&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-source&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-syms&distro=openSUSE%20Leap%2016.0pkg:rpm/opensuse/kernel-zfcpdump&distro=openSUSE%20Leap%2016.0
>= 5.11.0, < 6.12.95+ 13 more
- (no CPE)range: >= 5.11.0, < 6.12.95
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1.160000.2.19
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
- (no CPE)range: < 6.12.0-160000.37.1
Patches
Vulnerability mechanics
References
4News mentions
1- Linux Kernel: 25 Vulnerabilities Across Subsystems Disclosed TogetherVypr Intelligence · Jul 20, 2026