PatchTheCVECVE-2026-8452: Citrix NetScaler ADC and NetScaler Gateway Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability
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CRITICAL 9.8EXPLOITEDREMOTEUPGRADEUPGRADE
CVE-2026-8452 is a critical-severity flaw (CVSS 9.8) affecting netscaler application delivery controller, netscaler gateway, reported as exploited in the wild. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Memory overflow vulnerability NetScaler ADC and NetScaler Gateway leading to unpredictable or erroneous behavior and Denial of Service if the appliance is configured as a Gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server
Why this priority
- Critical severity
- Exploited in the wild (CISA KEV)
- Public exploit reference
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 1.0% (top 37%) |
| CISA exploited list | Yes, fix due 2026-08-29 |
| Weakness | CWE-119 |
| Published | 2026-06-30 |
| Last modified | 2026-08-27 |
Am I affected?
Timeline
- Published CVE record published
- Exploited Added to the CISA Known Exploited Vulnerabilities list
- Updated Record last modified
- Deadline CISA due date for US federal agencies to patch
citrix netscaler application delivery controller UPGRADE
Affected: < 13.1-37.272 · >= 13.1 and < 13.1-63.18 · >= 14.1 and < 14.1-72.61 · 14.1-66.68
Fixed in: 13.1-37.272, 13.1-63.18, 14.1-72.61
Safe to downgrade to: a release before 13.1
1. Check installed version
apt-cache policy netscaler-application-delivery-controller || rpm -q netscaler-application-delivery-controller || netscaler-application-delivery-controller --version
2. UPGRADE to 13.1-37.272 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade netscaler-application-delivery-controller
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade netscaler-application-delivery-controller
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before 13.1 (Debian / Ubuntu)
apt-cache madison netscaler-application-delivery-controller
sudo apt install netscaler-application-delivery-controller=<VERSION_BEFORE_13.1>
sudo apt-mark hold netscaler-application-delivery-controller
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list netscaler-application-delivery-controller
sudo dnf downgrade netscaler-application-delivery-controller-<VERSION_BEFORE_13.1>
sudo dnf versionlock add netscaler-application-delivery-controller
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
citrix netscaler gateway UPGRADE
Affected: >= 13.1 and < 13.1-63.18 · >= 14.1 and < 14.1-72.61
Fixed in: 13.1-63.18, 14.1-72.61
Safe to downgrade to: a release before 13.1
1. Check installed version
apt-cache policy netscaler-gateway || rpm -q netscaler-gateway || netscaler-gateway --version
2. UPGRADE to 13.1-63.18 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade netscaler-gateway
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade netscaler-gateway
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before 13.1 (Debian / Ubuntu)
apt-cache madison netscaler-gateway
sudo apt install netscaler-gateway=<VERSION_BEFORE_13.1>
sudo apt-mark hold netscaler-gateway
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list netscaler-gateway
sudo dnf downgrade netscaler-gateway-<VERSION_BEFORE_13.1>
sudo dnf versionlock add netscaler-gateway
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
Exact fixes by distribution
Fedora 46 · retext · FIXED · 8.1.0-1.fc46 · FEDORA-2026-0602a84203 · source
sudo dnf upgrade --advisory=FEDORA-2026-0602a84203
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- GitHub PoC: securekomodo/citrixInspector (96 stars)
- GitHub PoC: watchtowrlabs/watchTowr-vs-Citrix-Netscaler-PreAuth-RCE-CVE-2026-8452 (65 stars)
- GitHub PoC: BishopFox/CVE-2026-8452-check (1 stars)
Advisories and coverage
Research and news
- watchTowr Labs: You’re Back In The Room (Citrix NetScaler Pre-Auth RCE CVE-2026-8452(?)) 2026-08-14
Verify at the official source NVD · CVE Program · CISA KEV catalog · 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.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
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