Zyxel ATP/USG FLEX/VPN CAPWAP Daemon buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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6.5$0-$5k0.00

Summaryinfo

A vulnerability was found in Zyxel ATP, USG FLEX and VPN. It has been rated as critical. The affected element is an unknown function of the component CAPWAP Daemon. Performing a manipulation results in buffer overflow. This vulnerability is cataloged as CVE-2023-34140. The attack must originate from the local network. There is no exploit available.

Detailsinfo

A vulnerability was found in Zyxel ATP, USG FLEX and VPN (Network Encryption Software) (version unknown). It has been classified as critical. This affects an unknown function of the component CAPWAP Daemon. 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 5.36 Patch 2, USG FLEX series firmware versions 4.50 through 5.36 Patch 2, USG FLEX 50(W) series firmware versions 4.16 through 5.36 Patch 2, USG20(W)-VPN series firmware versions 4.16 through 5.36 Patch 2, VPN series firmware versions 4.30 through 5.36 Patch 2, NXC2500 firmware versions 6.10(AAIG.0) through 6.10(AAIG.3), and NXC5500 firmware versions 6.10(AAOS.0) through 6.10(AAOS.4), could allow an unauthenticated, LAN-based attacker to cause denial of service (DoS) conditions by sending a crafted request to the CAPWAP daemon.

The weakness was shared 07/18/2023. It is possible to read the advisory at zyxel.com. This vulnerability is uniquely identified as CVE-2023-34140 since 05/26/2023. 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 07/18/2023).

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

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Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.5

VulDB Base Score: 6.5
VulDB Temp Score: 6.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 6.5
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: No
Local: No
Remote: Partially

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

05/26/2023 🔍
07/18/2023 +53 days 🔍
07/18/2023 +0 days 🔍
07/18/2023 +0 days 🔍

Sourcesinfo

Vendor: zyxel.com

Advisory: zyxel.com
Status: Confirmed

CVE: CVE-2023-34140 (🔍)
GCVE (CVE): GCVE-0-2023-34140
GCVE (VulDB): GCVE-100-234339

Entryinfo

Created: 07/18/2023 09:57
Changes: 07/18/2023 09:57 (48)
Complete: 🔍
Cache ID: 216::103

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