ZyXEL NAS540 Telnet privileges management

CVSS Meta Temp Score
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CTI Interest Score
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6.8$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in ZyXEL NSA310, NSA320S, NSA221, NSA325, NAS326, NAS542, NAS520 and NAS540. This affects an unknown function of the component Telnet Handler. This manipulation causes privileges management. This vulnerability appears as CVE-2020-13365. The attack requires local access. There is no available exploit.

Detailsinfo

A vulnerability was found in ZyXEL NSA310, NSA320S, NSA221, NSA325, NAS326, NAS542, NAS520 and NAS540. It has been declared as critical. Affected by this vulnerability is some unknown functionality of the component Telnet Handler. The manipulation with an unknown input leads to a privileges management vulnerability. The CWE definition for the vulnerability is CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Certain Zyxel products have a locally accessible binary that allows a non-root user to generate a password for an undocumented user account that can be used for a TELNET session as root. This affects NAS520 V5.21(AASZ.4)C0, V5.21(AASZ.0)C0, V5.11(AASZ.3)C0, and V5.11(AASZ.0)C0; NAS542 V5.11(ABAG.0)C0, V5.20(ABAG.1)C0, and V5.21(ABAG.3)C0; NSA325 v2_V4.81(AALS.0)C0 and V4.81(AAAJ.1)C0; NSA310 4.22(AFK.0)C0 and 4.22(AFK.1)C0; NAS326 V5.21(AAZF.8)C0, V5.11(AAZF.4)C0, V5.11(AAZF.2)C0, and V5.11(AAZF.3)C0; NSA310S V4.75(AALH.2)C0; NSA320S V4.75(AANV.2)C0 and V4.75(AANV.1)C0; NSA221 V4.41(AFM.1)C0; and NAS540 V5.21(AATB.5)C0 and V5.21(AATB.3)C0.

The weakness was presented 08/06/2020. This vulnerability is known as CVE-2020-13365 since 05/21/2020. Attacking locally is a requirement. A single authentication is required for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

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

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Productinfo

Vendor

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License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.8

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.4
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Privileges management
CWE: CWE-269 / CWE-266
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

05/21/2020 🔍
08/06/2020 +77 days 🔍
08/07/2020 +1 days 🔍
11/07/2020 +92 days 🔍

Sourcesinfo

Vendor: zyxel.com

Status: Not defined

CVE: CVE-2020-13365 (🔍)
GCVE (CVE): GCVE-0-2020-13365
GCVE (VulDB): GCVE-100-159343

Entryinfo

Created: 08/07/2020 08:32
Updated: 11/07/2020 09:49
Changes: 08/07/2020 08:32 (35), 08/07/2020 08:37 (11), 11/07/2020 09:49 (1)
Complete: 🔍
Cache ID: 216::103

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