How to Fix CVE-2026-35237: Access control in MySQL Server
By Sai Kiran Pandrala. Last verified: 2026-05-25.
| Severity | 4.9 (Medium) |
|---|---|
| Actively exploited? | No public listing in CISA KEV |
| Affected | Oracle Corporation MySQL Server 8.0.0 to <8.0.45, 8.4.0 to <8.4.8, 9.0.0 to <9.6.0 |
| Fixed in | MySQL Server 8.0.45; MySQL Server 8.4.8; MySQL Server 9.6.0 |
| Type (CWE) | CWE-284: Improper Access Control |
What is CVE-2026-35237?
Vulnerability in the MySQL Server product of Oracle MySQL (component: InnoDB). Supported versions that are affected are 8.0.0-8.0.45, 8.4.0-8.4.8 and 9.0.0-9.6.0. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server.
Am I affected?
Run the version check that matches your platform:
# Linux
dpkg -s mysql-server 2>/dev/null | grep -i version
rpm -q mysql-server 2>/dev/null
mysql-server --version 2>/dev/null
Compare what you see against the Affected row above (Oracle Corporation MySQL Server 8.0.0 to <8.0.45, 8.4.0 to <8.4.8, 9.0.0 to <9.6.0). If your build sits inside that range, you are exposed and should patch.
How to fix CVE-2026-35237
The primary fix is to upgrade MySQL Server to the patched build. Use the commands for your platform below; the patched versions listed in the vendor advisory are: MySQL Server 8.0.45; MySQL Server 8.4.8; MySQL Server 9.6.0.
Ubuntu / Debian
sudo apt-get update
sudo apt-get install --only-upgrade mysql-server
mysql-server --version 2>/dev/null || dpkg -s mysql-server | grep -i version
RHEL / CentOS / Rocky / AlmaLinux
sudo dnf upgrade --security mysql-server -y
rpm -q mysql-server
SUSE / openSUSE
sudo zypper patch --category security
rpm -q mysql-server
Complete PowerShell remediation script (Windows)
# Fix script for CVE-2026-35237 affecting MySQL
# Run as administrator. Detect -> backup -> upgrade -> verify -> log.
$ErrorActionPreference = "Stop"
$LogPath = "C:\Logs\CVE-2026-35237-fix-$(Get-Date -Format yyyyMMdd-HHmmss).log"
New-Item -ItemType Directory -Force (Split-Path $LogPath) | Out-Null
Start-Transcript -Path $LogPath -Append
try {
Write-Host "[1/4] Detecting installed version of MySQL"
$pkg = winget list --id "MySQL" 2>$null
Write-Host $pkg
Write-Host "[2/4] Backing up configuration"
$backup = "C:\Backup\MySQL-$(Get-Date -Format yyyyMMdd)"
New-Item -ItemType Directory -Force $backup | Out-Null
Get-ChildItem "C:\ProgramData\MySQL" -ErrorAction SilentlyContinue |
Copy-Item -Destination $backup -Recurse -Force -ErrorAction SilentlyContinue
Write-Host "[3/4] Applying upgrade to MySQL Server 8.0.45; MySQL Server 8.4.8; MySQL Server 9.6.0"
winget upgrade --id "MySQL" --silent --accept-source-agreements --accept-package-agreements
# Fallback: Windows Update for OS-level fixes
if ($LASTEXITCODE -ne 0) {
Install-Module -Name PSWindowsUpdate -Force -SkipPublisherCheck -ErrorAction SilentlyContinue
Import-Module PSWindowsUpdate
Install-WindowsUpdate -MicrosoftUpdate -AcceptAll -IgnoreReboot
}
Write-Host "[4/4] Verifying patched build"
winget list --id "MySQL"
Write-Host "Fix applied. Reboot if prompted."
exit 0
} catch {
Write-Error "Patch failed: $_"
exit 1
} finally {
Stop-Transcript
}
Complete Bash remediation script (Linux)
#!/usr/bin/env bash
# Fix script for CVE-2026-35237 affecting MySQL
# Detect -> backup -> upgrade -> verify -> log.
set -euo pipefail
LOG="/var/log/cve-2026-35237-fix-$(date +%Y%m%d-%H%M%S).log"
exec > >(tee -a "$LOG") 2>&1
echo "[1/4] Detecting installed version"
if command -v dpkg >/dev/null; then
dpkg -s mysql-server 2>/dev/null | grep -i version || echo "mysql-server not installed via dpkg"
elif command -v rpm >/dev/null; then
rpm -q mysql-server || echo "mysql-server not installed via rpm"
fi
echo "[2/4] Backing up configuration"
BACKUP="/root/backup-cve-2026-35237-$(date +%Y%m%d)"
mkdir -p "$BACKUP"
for d in /etc/mysql-server /etc/mysql-server.d /etc/mysql-server.conf; do
[ -e "$d" ] && cp -a "$d" "$BACKUP/" || true
done
echo "[3/4] Applying upgrade (target: MySQL Server 8.0.45; MySQL Server 8.4.8; MySQL Server 9.6.0)"
if command -v apt-get >/dev/null; then
apt-get update
apt-get install --only-upgrade -y mysql-server
elif command -v dnf >/dev/null; then
dnf upgrade --security -y mysql-server
elif command -v yum >/dev/null; then
yum update -y mysql-server
elif command -v zypper >/dev/null; then
zypper --non-interactive patch --category security
fi
echo "[4/4] Verifying patched build"
if command -v dpkg >/dev/null; then
dpkg -s mysql-server 2>/dev/null | grep -i version
elif command -v rpm >/dev/null; then
rpm -q mysql-server
fi
echo "Done. Restart any running daemons that loaded the old library."
If you can't patch immediately
If you cannot apply the patched version today, restrict exposure with one of the following runnable controls. None replace the patch.
Network restriction (Linux, nftables)
# Block inbound traffic to the affected service from untrusted networks
sudo nft add table inet filter
sudo nft 'add chain inet filter input { type filter hook input priority 0 ; }'
sudo nft 'add rule inet filter input tcp dport {443, 80} ip saddr != 10.0.0.0/8 drop'
sudo nft list ruleset
Service-level fallback
# If the affected feature is optional, stop the service until the patch is applied
sudo systemctl stop mysql-server
sudo systemctl disable mysql-server
How to verify the fix worked
# Linux
mysql-server --version 2>/dev/null || dpkg -s mysql-server | grep -i version
rpm -q mysql-server 2>/dev/null || true
# Windows
winget list | findstr /I "mysql-server"
Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 5
Expected: the reported version is at or above MySQL Server 8.0.45; MySQL Server 8.4.8; MySQL Server 9.6.0. Restart any services that loaded the old library (systemctl restart <service> on Linux, restart the Windows service or reboot when prompted). For network appliances, run show version on the device and confirm the build matches the patched release.
Frequently asked questions
Related fixes
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- How to Fix CVE-2026-34289: Oracle Identity Manager Connector (Bundle Sibling) — Oracle Identity Manager Connector (Bundle Sibling)
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Is CVE-2026-35237 actually being exploited?
According to the data sources above, no public confirmation of in-the-wild exploitation at this time. Either way, the fix is the same: apply the vendor patch.
Do I need to reboot after patching?
For OS or kernel updates, yes. For most userland packages a systemctl restart <service> is enough. Any process that loaded the old shared library keeps using it until restarted, so when in doubt, reboot.
What is the CVSS score?
4.9 (medium). Refer to the vendor advisory for the exact vector string.
Where is the official advisory?
See the References section at the bottom of this page; the vendor's URL is the authoritative source for affected builds and patched versions.
References
- Official vendor advisory: https://www.oracle.com/security-alerts/cpuapr2026.html
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-35237
*Written by Sai Kiran Pandrala. Assembled from the official vendor advisory, NVD record, and CISA KEV listing on 2026-05-25. Always confirm against the vendor's advisory before applying changes in production.*