CVE-2020-13365

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.

CVSS v3.0 8.8 HIGH
CVSS v2.0 9.0 HIGH

8.8^/10

CVSS v3.0 : HIGH

V3 Legend

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

9.0^/10

CVSS v2.0 : HIGH

V2 Legend

Vector : AV:N/AC:L/Au:S/C:C/I:C/A:C

Exploitability : 8.0 / Impact : 10.0

Access Vector NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://www.zyxel.com/us/en/support/security_advisories.shtml	Vendor Advisory
https://www.zyxel.com/support/Zyxel-security-advisory-for-NAS-remote-access-vulnerability.shtml	Vendor Advisory

Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:zyxel:nas326_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:zyxel:nas326:-:*:*:*:*:*:*:*

Configuration 2 (hide)

AND

cpe:2.3:o:zyxel:nas520_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:zyxel:nas520:-:*:*:*:*:*:*:*

Configuration 3 (hide)

AND

cpe:2.3:o:zyxel:nas540_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:zyxel:nas540:-:*:*:*:*:*:*:*

Configuration 4 (hide)

AND

cpe:2.3:o:zyxel:nas542_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:zyxel:nas542:-:*:*:*:*:*:*:*

Information

Published : 2020-08-06 10:15

Updated : 2022-02-09 08:51

NVD link : CVE-2020-13365

Mitre link : CVE-2020-13365

JSON object : View

CWE

CWE-287

Improper Authentication

Products Affected

zyxel

nas326
nas542
nas520_firmware
nas540_firmware
nas520
nas540
nas326_firmware
nas542_firmware

{"cve": {"data_type": "CVE", "references": {"reference_data": [{"url": "https://www.zyxel.com/us/en/support/security_advisories.shtml", "name": "https://www.zyxel.com/us/en/support/security_advisories.shtml", "tags": ["Vendor Advisory"], "refsource": "MISC"}, {"url": "https://www.zyxel.com/support/Zyxel-security-advisory-for-NAS-remote-access-vulnerability.shtml", "name": "https://www.zyxel.com/support/Zyxel-security-advisory-for-NAS-remote-access-vulnerability.shtml", "tags": ["Vendor Advisory"], "refsource": "MISC"}]}, "data_format": "MITRE", "description": {"description_data": [{"lang": "en", "value": "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."}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "en", "value": "CWE-287"}]}]}, "data_version": "4.0", "CVE_data_meta": {"ID": "CVE-2020-13365", "ASSIGNER": "cve@mitre.org"}}, "impact": {"baseMetricV2": {"cvssV2": {"version": "2.0", "baseScore": 9.0, "accessVector": "NETWORK", "vectorString": "AV:N/AC:L/Au:S/C:C/I:C/A:C", "authentication": "SINGLE", "integrityImpact": "COMPLETE", "accessComplexity": "LOW", "availabilityImpact": "COMPLETE", "confidentialityImpact": "COMPLETE"}, "severity": "HIGH", "acInsufInfo": false, "impactScore": 10.0, "obtainAllPrivilege": false, "exploitabilityScore": 8.0, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}, "baseMetricV3": {"cvssV3": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.8, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.8}}, "publishedDate": "2020-08-06T17:15Z", "configurations": {"nodes": [{"children": [{"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:zyxel:nas326_firmware:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndExcluding": "v5.21\\(aazf.9\\)c0"}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:h:zyxel:nas326:-:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": false}]}], "operator": "AND", "cpe_match": []}, {"children": [{"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:zyxel:nas520_firmware:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndExcluding": "v5.21\\(aasz.5\\)c0"}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:h:zyxel:nas520:-:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": false}]}], "operator": "AND", "cpe_match": []}, {"children": [{"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:zyxel:nas540_firmware:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndExcluding": "v5.21\\(aatb.6\\)c0"}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:h:zyxel:nas540:-:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": false}]}], "operator": "AND", "cpe_match": []}, {"children": [{"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:o:zyxel:nas542_firmware:*:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": true, "versionEndExcluding": "v5.21\\(abag.6\\)c0"}]}, {"children": [], "operator": "OR", "cpe_match": [{"cpe23Uri": "cpe:2.3:h:zyxel:nas542:-:*:*:*:*:*:*:*", "cpe_name": [], "vulnerable": false}]}], "operator": "AND", "cpe_match": []}], "CVE_data_version": "4.0"}, "lastModifiedDate": "2022-02-09T16:51Z"}

8.8 /10