Zyxel ATP/USG FLEX/USG FLEX 50/USG20-VPN/VPN CLI Command buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.5$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Zyxel ATP, USG FLEX, USG FLEX 50, USG20-VPN and VPN. The impacted element is an unknown function of the component CLI Command Handler. Performing a manipulation results in buffer overflow. This vulnerability is identified as CVE-2023-37926. The attack is only possible with local access. There is not any exploit available.

Detailsinfo

A vulnerability classified as critical has been found in Zyxel ATP, USG FLEX, USG FLEX 50, USG20-VPN and VPN (Network Encryption Software). This affects some unknown processing of the component CLI Command Handler. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on availability. The summary by CVE is:

A buffer overflow vulnerability in the Zyxel ATP series firmware versions 4.32 through 5.37, USG FLEX series firmware versions 4.50 through 5.37, USG FLEX 50(W) series firmware versions 4.16 through 5.37, USG20(W)-VPN series firmware versions 4.16 through 5.37, and VPN series firmware versions 4.30 through 5.37, could allow an authenticated local attacker to cause denial-of-service (DoS) conditions by executing the CLI command to dump system logs on an affected device.

The weakness was released 11/28/2023. It is possible to read the advisory at zyxel.com. This vulnerability is uniquely identified as CVE-2023-37926 since 07/11/2023. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/28/2023).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.5
VulDB Temp Score: 5.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 5.5
CNA Vector (Zyxel Corporation): 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

07/11/2023 🔍
11/28/2023 +140 days 🔍
11/28/2023 +0 days 🔍
11/28/2023 +0 days 🔍

Sourcesinfo

Vendor: zyxel.com

Advisory: zyxel.com
Status: Confirmed

CVE: CVE-2023-37926 (🔍)
GCVE (CVE): GCVE-0-2023-37926
GCVE (VulDB): GCVE-100-246231

Entryinfo

Created: 11/28/2023 07:59
Changes: 11/28/2023 07:59 (48)
Complete: 🔍
Cache ID: 216::103

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