CVE-2021-40539

Zoho ManageEngine: ADSelfService Plus Authentication Bypass

As of , CVE-2021-40539 in Zoho ManageEngine is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.

Exploited
Yes: CISA listed it on 3 November 2021
US federal deadline
17 November 202114 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Known
EPSS score
0.99Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
Not availableCISA listed it before 4 February 2022, where the EPSS files we read begin.
Public exploit
1 Metasploit module
Fix
No vendor link in CISA's entry

What CISA says to do

Apply updates per vendor instructions.

CISA's required action

What the flaw is

Zoho ManageEngine ADSelfService Plus contains an authentication bypass vulnerability affecting the REST API URLs which allow for remote code execution.

CISA's description

Zoho ManageEngine ADSelfService Plus version 6113 and prior is vulnerable to REST API authentication bypass with resultant remote code execution.

The CVE record's description, from mitre

CVE published
7 September 2021
Assigned by
mitre
CVSS
9.8 Critical (CVSS 3.1, from CISA-ADP)
CWE-706
Use of Incorrectly-Resolved Name or Reference
CWE-55
Path Equivalence: '/./' (Single Dot Directory)
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

Public exploits

Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.

  • Metasploit: ManageEngine ADSelfService Plus CVE-2021-40539exploit module, rank excellent

ManageEngine: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2020-10189Desktop Central File UploadZoho ManageEnginePatch this weekMetasploit module; EPSS 0.99; verified Exploit-DB entry0.99
CVE-2022-28810ADSelfService Plus Remote Code ExecutionZoho ManageEnginePatch this weekMetasploit module; EPSS 0.710.71
CVE-2022-47966Multiple Products Remote Code ExecutionZoho ManageEnginePatch this weekRansomware use; Metasploit module; EPSS 0.990.99
CVE-2022-35405Multiple Products Remote Code ExecutionZoho ManageEnginePatch this weekMetasploit module; EPSS 0.990.99
CVE-2019-8394ServiceDesk Plus (SDP) File UploadZoho ManageEnginePatch this weekMetasploit module; EPSS 0.630.63

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