CVE-2023-33010

Exp

A buffer overflow vulnerability in the ID processing function in Zyxel ATP series firmware versions 4.32 through 5.36 Patch 1, USG FLEX series firmware versions 4.50 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.25 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.25 through 5.36 Patch 1, VPN series firmware versions 4.30 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.25 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.

Published: 2023-05-24 Last update: 2025-10-27 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-33010 is rated Critical Active Threat (97.8/100): CVSS Critical severity, with high exploitation likelihood (EPSS 7.32%, 92th percentile). CISA KEV confirms active exploitation (added 2023-06-05) affecting Zyxel / Multiple Firewalls. a weakness (CWE-120) Unauthenticated remote administrative access may be possible. EPSS rose +1.46% over the last day, indicating growing attacker interest. The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2023-33010

Name: Zyxel Multiple Firewalls Buffer Overflow Vulnerability · CISA KEV detail

Exploit added: 2023-06-05

Action due: 2023-06-26

Required action: Apply updates per vendor instructions.

Exploit prediction scoring system (EPSS) score for CVE-2023-33010

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-25 5.85% 7.32% +1.46%
2 2026-02-16 5.85% 5.85% +0.01%
3 2025-11-21 — 5.85% —

Full EPSS history (30 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-33010

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]

Weakness enumeration for CVE-2023-33010

Affected software / configurations for CVE-2023-33010

Vendor Product Version Raw CPE
zyxel atp100_firmware >= 4.32, < 5.36 cpe:2.3:o:zyxel:atp100_firmware:*:*:*:*:*:*:*:*
zyxel atp100_firmware 5.36 cpe:2.3:o:zyxel:atp100_firmware:5.36:-:*:*:*:*:*:*
zyxel atp100_firmware 5.36 cpe:2.3:o:zyxel:atp100_firmware:5.36:patch1:*:*:*:*:*:*
zyxel atp200_firmware >= 4.32, < 5.36 cpe:2.3:o:zyxel:atp200_firmware:*:*:*:*:*:*:*:*
zyxel atp200_firmware 5.36 cpe:2.3:o:zyxel:atp200_firmware:5.36:-:*:*:*:*:*:*
zyxel atp200_firmware 5.36 cpe:2.3:o:zyxel:atp200_firmware:5.36:patch1:*:*:*:*:*:*
zyxel atp500_firmware >= 4.32, < 5.36 cpe:2.3:o:zyxel:atp500_firmware:*:*:*:*:*:*:*:*
zyxel atp500_firmware 5.36 cpe:2.3:o:zyxel:atp500_firmware:5.36:-:*:*:*:*:*:*
zyxel atp500_firmware 5.36 cpe:2.3:o:zyxel:atp500_firmware:5.36:patch1:*:*:*:*:*:*
zyxel atp100w_firmware >= 4.32, < 5.36 cpe:2.3:o:zyxel:atp100w_firmware:*:*:*:*:*:*:*:*
zyxel atp100w_firmware 5.36 cpe:2.3:o:zyxel:atp100w_firmware:5.36:-:*:*:*:*:*:*
zyxel atp100w_firmware 5.36 cpe:2.3:o:zyxel:atp100w_firmware:5.36:patch1:*:*:*:*:*:*
zyxel atp700_firmware >= 4.32, < 5.36 cpe:2.3:o:zyxel:atp700_firmware:*:*:*:*:*:*:*:*
zyxel atp700_firmware 5.36 cpe:2.3:o:zyxel:atp700_firmware:5.36:-:*:*:*:*:*:*
zyxel atp700_firmware 5.36 cpe:2.3:o:zyxel:atp700_firmware:5.36:patch1:*:*:*:*:*:*
zyxel atp800_firmware >= 4.32, < 5.36 cpe:2.3:o:zyxel:atp800_firmware:*:*:*:*:*:*:*:*
zyxel atp800_firmware 5.36 cpe:2.3:o:zyxel:atp800_firmware:5.36:-:*:*:*:*:*:*
zyxel atp800_firmware 5.36 cpe:2.3:o:zyxel:atp800_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg_flex_100_firmware >= 4.50, < 5.36 cpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:*
zyxel usg_flex_100_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_100_firmware:5.36:-:*:*:*:*:*:*
zyxel usg_flex_100_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_100_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg_flex_50_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_50_firmware:5.36:-:*:*:*:*:*:*
zyxel usg_flex_50_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_50_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg_flex_200_firmware >= 4.50, < 5.36 cpe:2.3:o:zyxel:usg_flex_200_firmware:*:*:*:*:*:*:*:*
zyxel usg_flex_200_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_200_firmware:5.36:-:*:*:*:*:*:*
zyxel usg_flex_200_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_200_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg_flex_500_firmware >= 4.50, < 5.36 cpe:2.3:o:zyxel:usg_flex_500_firmware:*:*:*:*:*:*:*:*
zyxel usg_flex_500_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_500_firmware:5.36:-:*:*:*:*:*:*
zyxel usg_flex_500_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_500_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg_flex_700_firmware >= 4.50, < 5.36 cpe:2.3:o:zyxel:usg_flex_700_firmware:*:*:*:*:*:*:*:*
zyxel usg_flex_700_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_700_firmware:5.36:-:*:*:*:*:*:*
zyxel usg_flex_700_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_700_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg_flex_100w_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_100w_firmware:5.36:-:*:*:*:*:*:*
zyxel usg_flex_100w_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_100w_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg_flex_50w_firmware >= 4.25, < 5.36 cpe:2.3:o:zyxel:usg_flex_50w_firmware:*:*:*:*:*:*:*:*
zyxel usg_flex_50w_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_50w_firmware:5.36:-:*:*:*:*:*:*
zyxel usg_flex_50w_firmware 5.36 cpe:2.3:o:zyxel:usg_flex_50w_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg_20w-vpn_firmware 5.36 cpe:2.3:o:zyxel:usg_20w-vpn_firmware:5.36:-:*:*:*:*:*:*
zyxel usg_20w-vpn_firmware 5.36 cpe:2.3:o:zyxel:usg_20w-vpn_firmware:5.36:patch1:*:*:*:*:*:*
zyxel vpn100_firmware >= 4.30, < 5.36 cpe:2.3:o:zyxel:vpn100_firmware:*:*:*:*:*:*:*:*
zyxel vpn100_firmware 5.36 cpe:2.3:o:zyxel:vpn100_firmware:5.36:-:*:*:*:*:*:*
zyxel vpn100_firmware 5.36 cpe:2.3:o:zyxel:vpn100_firmware:5.36:patch1:*:*:*:*:*:*
zyxel vpn50_firmware >= 4.30, < 5.36 cpe:2.3:o:zyxel:vpn50_firmware:*:*:*:*:*:*:*:*
zyxel vpn50_firmware 5.36 cpe:2.3:o:zyxel:vpn50_firmware:5.36:-:*:*:*:*:*:*
zyxel vpn50_firmware 5.36 cpe:2.3:o:zyxel:vpn50_firmware:5.36:patch1:*:*:*:*:*:*
zyxel vpn300_firmware >= 4.30, < 5.36 cpe:2.3:o:zyxel:vpn300_firmware:*:*:*:*:*:*:*:*
zyxel vpn300_firmware 5.36 cpe:2.3:o:zyxel:vpn300_firmware:5.36:-:*:*:*:*:*:*
zyxel vpn300_firmware 5.36 cpe:2.3:o:zyxel:vpn300_firmware:5.36:patch1:*:*:*:*:*:*
zyxel vpn1000_firmware >= 4.30, < 5.36 cpe:2.3:o:zyxel:vpn1000_firmware:*:*:*:*:*:*:*:*
zyxel vpn1000_firmware 5.36 cpe:2.3:o:zyxel:vpn1000_firmware:5.36:-:*:*:*:*:*:*
zyxel vpn1000_firmware 5.36 cpe:2.3:o:zyxel:vpn1000_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg20-vpn_firmware >= 4.30, < 5.36 cpe:2.3:o:zyxel:usg20-vpn_firmware:*:*:*:*:*:*:*:*
zyxel usg20-vpn_firmware 5.36 cpe:2.3:o:zyxel:usg20-vpn_firmware:5.36:-:*:*:*:*:*:*
zyxel usg20-vpn_firmware 5.36 cpe:2.3:o:zyxel:usg20-vpn_firmware:5.36:patch1:*:*:*:*:*:*
zyxel usg_40_firmware >= 4.25, < 4.73 cpe:2.3:o:zyxel:usg_40_firmware:*:*:*:*:*:*:*:*
zyxel usg_40_firmware 4.73 cpe:2.3:o:zyxel:usg_40_firmware:4.73:-:*:*:*:*:*:*
zyxel usg_40_firmware 4.73 cpe:2.3:o:zyxel:usg_40_firmware:4.73:patch1:*:*:*:*:*:*
zyxel usg_40w_firmware >= 4.25, < 4.73 cpe:2.3:o:zyxel:usg_40w_firmware:*:*:*:*:*:*:*:*
zyxel usg_40w_firmware 4.73 cpe:2.3:o:zyxel:usg_40w_firmware:4.73:-:*:*:*:*:*:*
zyxel usg_40w_firmware 4.73 cpe:2.3:o:zyxel:usg_40w_firmware:4.73:patch1:*:*:*:*:*:*
zyxel usg_60w_firmware >= 4.25, < 4.73 cpe:2.3:o:zyxel:usg_60w_firmware:*:*:*:*:*:*:*:*
zyxel usg_60w_firmware 4.73 cpe:2.3:o:zyxel:usg_60w_firmware:4.73:-:*:*:*:*:*:*
zyxel usg_60w_firmware 4.73 cpe:2.3:o:zyxel:usg_60w_firmware:4.73:patch1:*:*:*:*:*:*
zyxel usg_60_firmware >= 4.25, < 4.73 cpe:2.3:o:zyxel:usg_60_firmware:*:*:*:*:*:*:*:*
zyxel usg_60_firmware 4.73 cpe:2.3:o:zyxel:usg_60_firmware:4.73:-:*:*:*:*:*:*
zyxel usg_60_firmware 4.73 cpe:2.3:o:zyxel:usg_60_firmware:4.73:patch1:*:*:*:*:*:*

References for CVE-2023-33010

cvelogic Threat Intelligence