CVE-2023-6764
A format string vulnerability in a function of the IPSec VPN feature in Zyxel ATP...
A format string vulnerability in a function of the IPSec VPN feature in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1, USG FLEX series firmware versions from 4.50 through 5.37 Patch 1, USG FLEX 50(W) series firmware versions from 4.16 through 5.37 Patch 1, and USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1 could allow an attacker to achieve unauthorized remote code execution by sending a sequence of specially crafted payloads containing an invalid pointer; however, such an attack would require detailed knowledge of an affected device’s memory layout and configuration.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
A format string vulnerability in a function of the IPSec VPN feature in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1, USG FLEX series firmware versions from 4.50 through 5.37 Patch 1, USG FLEX 50(W) series firmware versions from 4.16 through 5.37 Patch 1, and USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1 could allow an attacker to achieve unauthorized remote code execution by sending a sequence of specially crafted payloads containing an invalid pointer; however, such an attack would require detailed knowledge of an affected device’s memory layout and configuration.
- Record
CVE-2023-6764- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-134
- Updated
- 2026-11-02
EUVDEUVD-2023-58976
A format string vulnerability in a function of the IPSec VPN feature in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1, USG FLEX series firmware versions from 4.50 through 5.37 Patch 1, USG FLEX 50(W) series firmware versions from 4.16 through 5.37 Patch 1, and USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1 could allow an attacker to achieve unauthorized remote code execution by sending a sequence of specially crafted payloads containing an invalid pointer; however, such an attack would require detailed knowledge of an affected device’s memory layout and configuration.
- Record
EUVD-2023-58976- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-83ff-cpf7-ghwf
A format string vulnerability in a function of the IPSec VPN feature in Zyxel ATP...
A format string vulnerability in a function of the IPSec VPN feature in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1, USG FLEX series firmware versions from 4.50 through 5.37 Patch 1, USG FLEX 50(W) series firmware versions from 4.16 through 5.37 Patch 1, and USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1 could allow an attacker to achieve unauthorized remote code execution by sending a sequence of specially crafted payloads containing an invalid pointer; however, such an attack would require detailed knowledge of an affected device’s memory layout and configuration.
- Record
GHSA-83ff-cpf7-ghwf- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-134
- Updated
- 2026-11-02
NVD
A format string vulnerability in a function of the IPSec VPN feature in Zyxel ATP series firmware versions from 4.32 through 5.37 Patch 1, USG FLEX series firmware versions from 4.50 through 5.37 Patch 1, USG FLEX 50(W) series firmware versions from 4.16 through 5.37 Patch 1, and USG20(W)-VPN series firmware versions from 4.16 through 5.37 Patch 1 could allow an attacker to achieve unauthorized remote code execution by sending a sequence of specially crafted payloads containing an invalid pointer; however, such an attack would require detailed knowledge of an affected device’s memory layout and configuration.
- Record
CVE-2023-6764- CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-134
- Updated
- 2026-11-02
Affected products
- zyxel atp series firmware
- zyxel usg flex 50(w) series firmware
- zyxel usg flex series firmware
- zyxel usg20(w)-vpn series firmware
- zyxel atp100 firmware
- zyxel atp100w firmware
- zyxel atp200 firmware
- zyxel atp500 firmware
- zyxel atp700 firmware
- zyxel atp800 firmware
- zyxel atp firmware
- zyxel usg20-vpn firmware
Show 16 moreShow less
- zyxel usg20w-vpn firmware
- zyxel usg 20w-vpn firmware
- zyxel usg flex 100 firmware
- zyxel usg flex 100ax firmware
- zyxel usg flex 100h firmware
- zyxel usg flex 100w firmware
- zyxel usg flex 200 firmware
- zyxel usg flex 200h firmware
- zyxel usg flex 200hp firmware
- zyxel usg flex 500 firmware
- zyxel usg flex 500h firmware
- zyxel usg flex 50 firmware
- zyxel usg flex 50w firmware
- zyxel usg flex 700 firmware
- zyxel usg flex 700h firmware
- zyxel usg flex firmware
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-6764 is a high vulnerability (CVSS 8.1) in Zyxel Atp Series Firmware, published February 20, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.89%, the 59th percentile. No source names a fixed version.