CVE-2023-28771

Critical
9.8
0.05.010.0
Year
2023
Published
Apr 25, 2023
Known Affected Devices
0
CVSS Score
9.8

What is CVE-2023-28771?

Improper error message handling in Zyxel ZyWALL/USG series firmware versions 4.60 through 4.73, VPN series firmware versions 4.60 through 5.35, USG FLEX series firmware versions 4.60 through 5.35, and ATP series firmware versions 4.60 through 5.35, which could allow an unauthenticated attacker to execute some OS commands remotely by sending crafted packets to an affected device.

CVSS Vector Breakdown

CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
AV
Attack Vector
Network

Exploitable remotely over the network without requiring access to the local system.

AC
Attack Complexity
Low

No special conditions required. Exploit can be performed reliably and repeatedly.

PR
Privileges Required
None

No authentication required. Any anonymous user can exploit this vulnerability.

UI
User Interaction
None

No user interaction required. Exploit runs without any victim action.

S
Scope
Unchanged

Exploiting the vulnerability only affects the vulnerable component itself.

C
Confidentiality Impact
High

Complete loss of confidentiality. All data on the component may be exposed.

I
Integrity Impact
High

Complete loss of integrity. Attacker can modify any file or data on the component.

A
Availability Impact
High

Complete denial of service. The component becomes fully unavailable.

Known Affected Devices

FAQ

How severe is CVE-2023-28771?

CVE-2023-28771 has a CVSS score of 9.8/10, rated as Critical. This is the highest severity level - immediate patching is strongly recommended.

What does the CVSS score mean for CVE-2023-28771?

CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2023-28771 scores 9.8/10 (Critical). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.

Which devices are affected by CVE-2023-28771?

The list of devices confirmed to be affected by CVE-2023-28771 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.

How do I fix or mitigate CVE-2023-28771?

Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.