CVE-2026-68819: Buffer over-read in Windows Network File System allows an unauthorized attacker to deny service over a network
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MEDIUM 5.9REMOTEWATCHLISTUPGRADEUPGRADEMITIGATE
CVE-2026-68819 is a medium-severity flaw (CVSS 5.9) affecting windows 10 1607, windows 10 1809, windows server 2012. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Buffer over-read in Windows Network File System allows an unauthorized attacker to deny service over a network.
Last updated 2026-08-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
Published CVE record published
Updated Record last modified
microsoft windows 10 1607 UPGRADE
Affected: < 10.0.14393.9418
Fixed in: 10.0.14393.9418
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows 10 1809 UPGRADE
Affected: < 10.0.17763.9115
Fixed in: 10.0.17763.9115
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows server 2012 MITIGATE
Affected: all versions · r2
Fixed in: no fixed release known
Safe to downgrade to: a release before r2
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows server 2016 UPGRADE
Affected: < 10.0.14393.9418
Fixed in: 10.0.14393.9418
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows server 2019 UPGRADE
Affected: < 10.0.17763.9115
Fixed in: 10.0.17763.9115
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows server 2022 UPGRADE
Affected: < 10.0.20348.5440
Fixed in: 10.0.20348.5440
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
Verify at the official sourceNVD · CVE Program · Report a problem with this page Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-68819?
windows 10 1607: upgrade to 10.0.14393.9418; windows 10 1809: upgrade to 10.0.17763.9115; windows server 2012: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2026-68819 being exploited?
CVE-2026-68819 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-68819 affect?
CVE-2026-68819 affects windows 10 1607, windows 10 1809, windows server 2012. Severity is medium (CVSS 5.9). Buffer over-read in Windows Network File System allows an unauthorized attacker to deny service over a network.
How urgent is CVE-2026-68819?
Priority 46/100. Remotely exploitable, no login, no user action; On your watchlist