Zyxel ATP/USG FLEX/USG FLEX 50/USG20-VPN IPSec VPN format string

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability has been found in Zyxel ATP, USG FLEX, USG FLEX 50 and USG20-VPN and classified as critical. This impacts an unknown function of the component IPSec VPN. This manipulation causes format string. This vulnerability is handled as CVE-2023-6399. The attack can only be done within the local network. There is not any exploit available.

Detailsinfo

A vulnerability was found in Zyxel ATP, USG FLEX, USG FLEX 50 and USG20-VPN (Network Encryption Software) (the affected version unknown). It has been declared as critical. Affected by this vulnerability is an unknown part of the component IPSec VPN. The manipulation with an unknown input leads to a format string vulnerability. The CWE definition for the vulnerability is CWE-134. The product uses a function that accepts a format string as an argument, but the format string originates from an external source. As an impact it is known to affect availability. The summary by CVE is:

A format string vulnerability 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 authenticated IPSec VPN user to cause DoS conditions against the “deviceid” daemon by sending a crafted hostname to an affected device if it has the “Device Insight” feature enabled.

The weakness was released 02/20/2024. It is possible to read the advisory at zyxel.com. This vulnerability is known as CVE-2023-6399 since 11/30/2023. 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 01/21/2025).

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

Statistical analysis made it clear that VulDB provides the best quality 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: 6.0
VulDB Meta Temp Score: 6.0

VulDB Base Score: 5.7
VulDB Temp Score: 5.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CNA Base Score: 5.7
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: Format string
CWE: CWE-134 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

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

11/30/2023 🔍
02/20/2024 +82 days 🔍
02/20/2024 +0 days 🔍
01/21/2025 +336 days 🔍

Sourcesinfo

Vendor: zyxel.com

Advisory: zyxel.com
Status: Confirmed

CVE: CVE-2023-6399 (🔍)
GCVE (CVE): GCVE-0-2023-6399
GCVE (VulDB): GCVE-100-254131

Entryinfo

Created: 02/20/2024 07:52
Updated: 01/21/2025 20:46
Changes: 02/20/2024 07:52 (48), 01/21/2025 20:46 (27)
Complete: 🔍
Cache ID: 216::103

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