PatchTheCVECVE-2026-70465: A buffer copy without checking size of input ('classic buffer overflow') vulnerability in Fortinet FortiClient
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HIGH 8.1REMOTEUPGRADE
CVE-2026-70465 is a high-severity flaw (CVSS 8.1) affecting forticlient. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
A buffer copy without checking size of input ('classic buffer overflow') vulnerability in Fortinet FortiClientWindows 7.4.0 through 7.4.3, FortiClientWindows 7.2.0 through 7.2.11 may allow an unauthenticated attacker in a position to alter or craft DNS responses to the targeted host to execute arbitrary code via malicious packets.
Why this priority
- High severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 8.1 (High) |
| Attack vector | Network (remote) |
| Attack complexity | High |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.5% (top 57%) |
| CISA exploited list | No |
| Weakness | CWE-120 |
| Published | 2026-08-12 |
| Last modified | 2026-10-23 |
Publisher (CNA): Fortinet, Inc. · Vendor: fortinet
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
fortinet forticlient UPGRADE
Affected: >= 7.2.0 and < 7.2.12 · >= 7.4.0 and < 7.4.4
Fixed in: 7.2.12, 7.4.4
Safe to downgrade to: a release before 7.2.0
1. Check installed version
apt-cache policy forticlient || rpm -q forticlient || forticlient --version
2. UPGRADE to 7.2.12 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade forticlient
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade forticlient
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 7.2.0 (Debian / Ubuntu)
apt-cache madison forticlient
sudo apt install forticlient=<VERSION_BEFORE_7.2.0>
sudo apt-mark hold forticlient
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list forticlient
sudo dnf downgrade forticlient-<VERSION_BEFORE_7.2.0>
sudo dnf versionlock add forticlient
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 · clementine · FIXED · 1.4.2-1.fc46 · FEDORA-2026-3e748ef4d3 · source
sudo dnf upgrade --advisory=FEDORA-2026-3e748ef4d3
Verify at the official source NVD · 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.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.