Vulnerability · CVE-2026-99216
CVE-2026-99216: Drivers: hv: Don't reset VMBus connection state on error/exit paths
Published Oct 28, 2026 · catalog updated Nov 2, 2026 · Linux Linux
Last checked Nov 4, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2026-99216. EPSS is 0.14%. Act only if a listed version of Linux Linux is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
Same product and reporting
- CVE-2026-99260 · Medium
- CVE-2026-99259 · Medium
- CVE-2026-99258 · High
- CVE-2026-99257 · Medium
- CVE-2026-99255 · Medium
- Severity
- High8.4
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.14%
- Remediation
- Advisory link
- Affected products
- Linux Kernel · linux kernel · vendor Linux Linux
In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: Don't reset VMBus connection state on error/exit paths In two places, current code forces vmbus_connection.conn_state to DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect() calls vmbus_initiate_unload(), which unloads the VMBus connection only if the conn_state is CONNECTED. Consequently, the connection remains and the Hyper-V host might continue to send messages or post VMBus interrupts. The problem was introduced in commit 74347a99e73ae ("x86/Hyper-V: Unload vmbus channel in hv panic callback"), in that vmbus_initiate_unload() started checking the current connection state before doing the unload. This commit removed some occurrences where conn_state was forced to DISCONNECTED, but these two remained, apparently due to an oversight at the time. Fix this by not forcing conn_state to DISCONNECTED during VMBus exit, or if a failure occurs when establishing the connection in the first place. Whatever value conn_state has at the time is then read by vmbus_initiate_unload() to determine if there is a connection to be unloaded.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- Linux Kernel5.7.0 → 5.10.273; 5.11.0 → 5.15.224; 5.16.0 → 6.1.191
- Linux Kernel5.7.0 → 6.18.59; 6.19.0 → 7.2.13
- linux kernelversion unspecified
- vendor Linux Linuxversion unspecified
How to fix CVE-2026-99216
Upgrade
CVE-2026-99216 lists a fix boundary at 5.10.273. Compare the installed build with that boundary before you change production.
Version check
Seen in 5.7.0 → 5.10.273; 5.11.0 → 5.15.224; 5.16.0 → 6.1.191 · 1 other packages on the advisory
Advisory
Open the bsi record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-99216. EPSS is 0.14%. Act only if a listed version of Linux Linux is installed.
Which versions are affected?
Compare what you have installed with Kernel 5.7.0 → 5.10.273; 5.11.0 → 5.15.224; 5.16.0 → 6.1.191; Kernel 5.7.0 → 6.18.59; 6.19.0 → 7.2.13. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.14%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Oct 28, 2026 · Tenable CVE Database
Detected
In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: Don't reset VMBus connection state on error/exit paths In two places, current code forces vmbus_connection.conn_state to DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect() calls vmbus_initiate_unload(), which unloads the VMBus connection only if the conn_state is CONNECTED. Consequently, the conn
Oct 28, 2026 · CVE.org
Updated
In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: Don't reset VMBus connection state on error/exit paths In two places, current code forces vmbus_connection.conn_state to DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect() calls vmbus_initiate_unload(), which unloads the VMBus connection only if the conn_state is CONNECTED. Consequently, the conn
Oct 30, 2026 · OpenSSF OSV / OSV Scanner
Fix available
Kernel fixed in 6.18.59; Kernel fixed in 7.2.13
Oct 30, 2026 · OpenSSF OSV / OSV Scanner
Fix available
Kernel fixed in 6.18.59; 6.19.0
Oct 30, 2026 · OpenSSF OSV / OSV Scanner
Updated
In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: Don't reset VMBus connection state on error/exit paths In two places, current code forces vmbus_connection.conn_state to DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect() calls vmbus_initiate_unload(), which unloads the VMBus connection only if the conn_state is CONNECTED. Consequently, the conn
Nov 2, 2026 · OpenSSF OSV / OSV Scanner
Fix available
Kernel fixed in 5.10.273; Kernel fixed in 5.15.224; Kernel fixed in 6.1.191; Kernel fixed in 6.6.161
Nov 2, 2026 · OpenSSF OSV / OSV Scanner
Fix available
Kernel fixed in 5.10.273; 5.11.0
Nov 2, 2026 · OpenSSF OSV / OSV Scanner
Updated
In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: Don't reset VMBus connection state on error/exit paths In two places, current code forces vmbus_connection.conn_state to DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect() calls vmbus_initiate_unload(), which unloads the VMBus connection only if the conn_state is CONNECTED. Consequently, the conn
Sources
- BSI CERT-BundGovernment advisoryCVE-2026-99216
Linux Kernel: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff
wid.cert-bund.de - CVE.orgVulnerability recordCVE-2026-99216
In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: Don't reset VMBus connection state on error/exit paths In two places, current code forces vmbus_connection.conn_state to DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect() calls
cve.org - FIRST EPSSExploitation probabilityCVE-2026-99216
30-day exploitation probability 0.14%
first.org - Linux Kernel CVEVendor advisoryCVE-2026-99216
From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: Don't reset VMBus connection state on error/exit paths In two places, current code forces vmbus_connection.conn_state to DISCONNECTED prior to calling
git.kernel.org - OpenSSF OSV / OSV ScannerPackage advisoryCVE-2026-99216
Drivers: hv: Don't reset VMBus connection state on error/exit paths
osv.dev - Tenable CVE DatabaseVulnerability recordCVE-2026-99216
In the Linux kernel, the following vulnerability has been resolved: Drivers: hv: Don't reset VMBus connection state on error/exit paths In two places, current code forces vmbus_connection.conn_state to DISCONNECTED prior to calling vmbus_disconnect(). But vmbus_disconnect() calls vmbus_initiate_unload(), which unloads the VMBus connection only if the conn_state is CONNECTED. Consequently, the conn
tenable.com
References
Freshness
Last verified in this catalog Nov 4, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- FIRST EPSSNov 4, 2026
- OpenSSF OSV / OSV ScannerNov 2, 2026
- BSI CERT-BundOct 30, 2026
- CVE.orgOct 28, 2026
- Linux Kernel CVEOct 28, 2026
- Tenable CVE DatabaseOct 28, 2026