How to Fix CVE-2026-28099: Cross-site scripting in UberSlider Ultra

By Sai Kiran Pandrala. Last verified: 2026-05-25.

CVE-2026-28099 is a cross-site scripting in LambertGroup UberSlider Ultra. The fix is to apply the vendor patch noted below.

What is CVE-2026-28099?

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in LambertGroup UberSlider Ultra uberSlider_ultra allows Reflected XSS.This issue affects UberSlider Ultra: from n/a through <= 2.3. The CVSS base score is 7.1 (High), which puts this in the upper risk band and warrants a fast patch cycle. The official advisory is at https://patchstack.com/database/Wordpress/Plugin/uberSlider_ultra/vulnerability/wordpress-uberslider-ultra-plugin-2-3-reflected-cross-site-scripting-xss-vulnerability?_s_id=cve.

Am I affected?

Check the version of UberSlider Ultra you are running and compare it against the Affected row above (UberSlider Ultra 0 to <=2.3). If your build sits inside the affected range, you must patch.

Run the version check that fits your platform:

# Linux package check
dpkg -s uberslider-ultra 2>/dev/null | grep -i ^Version
rpm -q uberslider-ultra 2>/dev/null
command -v uberslider-ultra >/dev/null && uberslider-ultra --version 2>/dev/null

# Windows (PowerShell)
Get-Package -Name "*UberSlider Ultra*" -ErrorAction SilentlyContinue | Select-Object Name, Version
winget list --name "UberSlider Ultra" 2>$null

How to fix CVE-2026-28099

Upgrade UberSlider Ultra to a patched build: See vendor advisory. The vendor advisory is the source of truth for the exact fixed version.

Ubuntu / Debian

sudo apt-get update
sudo apt-get install --only-upgrade uberslider-ultra
dpkg -s uberslider-ultra | grep -i ^Version

RHEL / CentOS / Rocky / AlmaLinux

sudo dnf upgrade --refresh uberslider-ultra -y
# or for older releases:
sudo yum update uberslider-ultra -y
rpm -q uberslider-ultra

SUSE / openSUSE

sudo zypper refresh
sudo zypper update uberslider-ultra
rpm -q uberslider-ultra

Node.js / npm

# Update the affected package in your project
npm install UberSlider Ultra@latest
npm ls UberSlider Ultra
npm audit fix

Complete PowerShell remediation script (Windows)

# Fix script for CVE-2026-28099 affecting UberSlider Ultra
# Run as administrator. Detect -> backup -> upgrade -> verify -> log.

$ErrorActionPreference = "Stop"
$LogPath  = "C:\Logs\CVE-2026-28099-fix-$(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] Detect installed version"
    $pkg = Get-Package -Name "*UberSlider Ultra*" -ErrorAction SilentlyContinue
    if ($pkg) { $pkg | Format-Table Name, Version }
    else { Write-Host "Not detected via Get-Package; try winget list" }

    Write-Host "[2/4] Backup configuration"
    $backup = "C:\Backup\uberslider-ultra-$(Get-Date -Format yyyyMMdd)"
    New-Item -ItemType Directory -Force $backup | Out-Null
    Get-ChildItem "C:\ProgramData\UberSlider Ultra" -ErrorAction SilentlyContinue |
        Copy-Item -Destination $backup -Recurse -Force -ErrorAction SilentlyContinue

    Write-Host "[3/4] Apply the upgrade to See vendor advisory"
    winget upgrade --name "UberSlider Ultra" --silent --accept-source-agreements --accept-package-agreements
    if ($LASTEXITCODE -ne 0) {
        # Fallback: pull latest via OS update channel
        Install-Module -Name PSWindowsUpdate -Force -SkipPublisherCheck -ErrorAction SilentlyContinue
        Import-Module PSWindowsUpdate
        Install-WindowsUpdate -MicrosoftUpdate -AcceptAll -IgnoreReboot
    }

    Write-Host "[4/4] Verify the patched build"
    winget list --name "UberSlider Ultra"
    Write-Host "Patch 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-2026-28099 affecting UberSlider Ultra
# Detect -> backup -> upgrade -> verify -> log.

set -euo pipefail
LOG="/var/log/cve-2026-28099-fix-$(date +%Y%m%d-%H%M%S).log"
exec > >(tee -a "$LOG") 2>&1

echo "[1/4] Detect installed version"
if command -v dpkg >/dev/null; then
    dpkg -s uberslider-ultra 2>/dev/null | grep -i ^Version || echo "uberslider-ultra not installed via dpkg"
elif command -v rpm >/dev/null; then
    rpm -q uberslider-ultra || echo "uberslider-ultra not installed via rpm"
fi

echo "[2/4] Backup configuration"
BACKUP="/root/backup-cve-2026-28099-$(date +%Y%m%d)"
mkdir -p "$BACKUP"
for d in /etc/uberslider-ultra /etc/uberslider-ultra.d /etc/uberslider-ultra.conf; do
    [ -e "$d" ] && cp -a "$d" "$BACKUP/" || true
done

echo "[3/4] Apply the upgrade (target: See vendor advisory)"
if command -v apt-get >/dev/null; then
    apt-get update
    apt-get install --only-upgrade -y uberslider-ultra
elif command -v dnf >/dev/null; then
    dnf upgrade --refresh -y uberslider-ultra
elif command -v yum >/dev/null; then
    yum update -y uberslider-ultra
elif command -v zypper >/dev/null; then
    zypper --non-interactive update uberslider-ultra
fi

echo "[4/4] Verify the patched build"
if command -v dpkg >/dev/null; then
    dpkg -s uberslider-ultra 2>/dev/null | grep -i ^Version
elif command -v rpm >/dev/null; then
    rpm -q uberslider-ultra
fi
echo "Done. Restart any service that loaded the old library."

If you can't patch immediately

Apply at least one of the following inline controls until you can deploy the patched build. None replace the upgrade.

Restrict exposure with nftables (Linux)

# Allow only trusted CIDR to reach the affected service ports
sudo nft add table inet filter 2>/dev/null || true
sudo nft 'add chain inet filter input { type filter hook input priority 0 ; }' 2>/dev/null || true
sudo nft 'add rule inet filter input tcp dport {80, 443} ip saddr != 10.0.0.0/8 drop'
sudo nft list ruleset

Block at the host firewall (Windows)

New-NetFirewallRule -DisplayName "Block-CVE-2026-28099" -Direction Inbound -Action Block -Protocol TCP -LocalPort 80,443 -RemoteAddress Any -Enabled True
Get-NetFirewallRule -DisplayName "Block-CVE-2026-28099"

Disable the affected service (Linux)

sudo systemctl stop uberslider-ultra 2>/dev/null || true
sudo systemctl disable uberslider-ultra 2>/dev/null || true

If the vendor advisory lists an official workaround, prefer that wording verbatim. If no workaround is published, the only safe remediation is the patch.

How to verify the fix worked

After upgrading, confirm the installed version matches the patched build and that no old library is still loaded by a long-running process.

# Linux
dpkg -s uberslider-ultra 2>/dev/null | grep -i ^Version
rpm -q uberslider-ultra 2>/dev/null || true
# Pid map check for old library handles
sudo lsof +c0 2>/dev/null | grep -i "DEL.*lib" || true

# Windows
Get-Package -Name "*UberSlider Ultra*" | Select-Object Name, Version
Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 5

Expected: the reported version is at or above See vendor advisory. Restart the affected service (systemctl restart <service> on Linux, or restart the Windows service) so it loads the patched binary.

Frequently asked questions

Related fixes

Other vulnerabilities in the same area that are worth patching alongside this one:

• How to Fix CVE-2026-25243: Heap-based Buffer Overflow in redis — Heap-based Buffer Overflow in redis
• How to Fix CVE-2026-35344: CWE-252: Unchecked Return Value in coreutils — CWE-252: Unchecked Return Value in coreutils
• How to Fix CVE-2026-32611: Glances has a SQL Injection in DuckDB Export via Unparameterized DDL Statements , Glances has a SQL Injection in DuckDB Export via Unparameterized DDL Statements
• How to Fix CVE-2026-1708: CWE-89 Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') , CWE-89 Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
• How to Fix CVE-2026-35570: Path traversal in openclaude , Path traversal in openclaude

Is CVE-2026-28099 actively exploited?

There is no public confirmation of exploitation in the wild listed in CISA KEV at the time of this writing. Patch anyway. Public exploits commonly follow disclosure within weeks.

Do I need to reboot after patching CVE-2026-28099?

For kernel and OS-level updates, yes. For most userland packages a systemctl restart <service> is enough on Linux, and restarting the Windows service or app on Windows. Any process that loaded the old library keeps using it until restarted.

What is the CVSS score for CVE-2026-28099?

7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L.

Where is the official advisory for CVE-2026-28099?

The vendor advisory is at https://patchstack.com/database/Wordpress/Plugin/uberSlider_ultra/vulnerability/wordpress-uberslider-ultra-plugin-2-3-reflected-cross-site-scripting-xss-vulnerability?_s_id=cve. The NVD record is at https://nvd.nist.gov/vuln/detail/CVE-2026-28099.

References

• Official vendor advisory: https://patchstack.com/database/Wordpress/Plugin/uberSlider_ultra/vulnerability/wordpress-uberslider-ultra-plugin-2-3-reflected-cross-site-scripting-xss-vulnerability?_s_id=cve
• NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-28099
• CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog

*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.*