Hackers exploiting vulnerability affecting Zoho ManageEngine products: Rapid7

CVE-2021-40539 is a critical (CVSS 9.8) authentication bypass in the REST API of Zoho ManageEngine ADSelfService Plus, caused by use of an incorrectly resolved name or reference (CWE-706). An unauthenticated, network-adjacent or internet-reachable attacker sends specially crafted requests to the product's REST API, bypassing authentication, and can chain the bypass to full remote code execution with no privileges or user interaction required. Successful exploitation yields complete compromise of the self-service portal server (high impact to confidentiality, integrity and availability); public reporting and vendor notes document attackers dropping malicious code and web shells onto vulnerable servers. Any organization running ManageEngine ADSelfService Plus build 6113 or earlier is affected, which typically means enterprise Microsoft Active Directory environments running this widely deployed self-service password/SSO portal. Exploitation is confirmed in the wild: the flaw was added to CISA KEV on 2021-11-03 with known ransomware use, EPSS puts the 30-day exploitation probability at 99% (100th percentile), Microsoft warned that Chinese threat actors were actively exploiting it, a public proof-of-concept is available, and it ranked among CISA's most routinely exploited vulnerabilities.

Do: Immediately upgrade ManageEngine ADSelfService Plus to a fixed build newer than 6113 per the vendor's update instructions, as required by CISA. Because exploitation predates patching and the flaw has been used to drop malicious code, check ADSelfService Plus servers for web shells, unexpected scheduled tasks, and unexplained accounts/processes, and hunt for indicators from the published analyses. Where possible, restrict internet exposure of the ADSelfService Plus REST API while patching, prioritized for externally reachable instances.

CVE-2022-47966 is a critical (CVSS 9.8), unauthenticated remote code execution flaw in roughly two dozen Zoho ManageEngine on-premise products caused by their bundled Apache Santuario xmlsec (XML Security for Java) 1.4.1 library, in which the XSLT features leave security protections to the application and ManageEngine did not provide them. An attacker triggers the flaw by sending a crafted SAML response containing a malicious XSLT transform to the SAML single sign-on (SSO) endpoint; exploitation is only possible if SAML SSO has ever been configured for the product (for some products, SAML SSO must be currently active). Successful exploitation yields arbitrary code execution in the context of the affected ManageEngine application, typically full compromise of the server and a foothold into the wider enterprise network. Any organization running an affected product version with SAML SSO enabled is affected, with internet-exposed ITSM/identity-management servers the most likely targets. Exploitation is confirmed in the wild: the flaw is in CISA KEV with known ransomware use, Rapid7 reported broad attacker interest, North Korea's Lazarus Group used it to deploy QuiteRAT, and Iranian government-backed actors have targeted U.S. energy and transit-sector organizations.

Do: Apply vendor updates immediately, upgrading each installed product to at least the fixed version listed (e.g., ServiceDesk Plus 14004+, ADSelfService Plus 6211+, Endpoint Central/Endpoint Central MSP 10.1.2228.11+, Password Manager Pro 12124+, ServiceDesk Plus MSP 13001+, ADAudit Plus 7081+, ADManager Plus 7162+, AD360 4310+); this is a CISA KEV required action. As an interim mitigation, disable or restrict SAML SSO (or limit access to the product's SSO endpoints), since SAML SSO must have been configured for exploitation. Prioritize patching internet-exposed instances and review those servers for signs of compromise, given documented use by Lazarus Group, ransomware operators, and Iranian nation-state actors.