CVE-2026-77697

Executive Summary

CVE-2026-77697 is a privilege escalation vulnerability in Zohocorp ManageEngine Endpoint Central, affecting all versions prior to 11.4.2540.23. The vulnerability is triggered during the JAR extraction process, allowing a local attacker with low privileges to escalate to a higher privilege level. Although it carries a CVSS score of 6.3 (Medium severity), the vulnerability's local attack vector and the privileged context in which Endpoint Central typically runs make it a significant concern for enterprises relying on this endpoint management platform.

Technical Analysis

The vulnerability is a privilege escalation flaw that manifests specifically during JAR extraction operations. JAR (Java Archive) files are commonly used across the ManageEngine platform for distributing updates, plugins, and configuration components. The extraction process is typically executed in the context of the service account running Endpoint Central, which frequently operates with elevated system-level privileges in enterprise deployments.

At the vulnerability-class level (CWE-269 — Improper Privilege Management), the flaw suggests that during the extraction of JAR archives, the application fails to adequately enforce or validate its privilege boundaries. An attacker who can supply or influence a JAR file that gets processed by the Endpoint Central service may be able to leverage the extraction routine to:

1. Write files to directories or paths with higher privilege requirements than the attacker's current access level permits
2. Overwrite or replace legitimate application files, configuration data, or executable components
3. Potentially place payloads into directories traversed during the extraction or subsequent loading operations

The local attack vector (AV:L) in the CVSS vector emphasizes that the attacker requires some level of existing local access — either an unprivileged user account on the managed endpoint/server or a foothold achieved through another compromise. The low attack complexity (AC:L) indicates the technique does not require specialized conditions or a race window that is difficult to predict; it is straightforward to trigger. The requirement for low privileges (PR:L) means a standard user account is sufficient to initiate the attack chain.

The user interaction requirement of NONE (UI:N) indicates the attack does not require a separate victim (such as an administrator) to perform any action for the exploitation to succeed. The scope change (S:C) in the CVSS vector is notable: the impact is not confined to the security context in which the vulnerable component runs — it can affect resources beyond the compromised component's authority, potentially granting the attacker access to other processes, files, or services running under higher privilege levels on the same host.

Confidentiality, Integrity, and Availability impacts are all rated as LOW (C:L/I:L/A:L), suggesting the vulnerability grants partial information disclosure, permits limited data modification, and may cause minor service degradation. It is worth noting that insufficient technical detail is available in the NVD description to specify precisely which JAR files are vulnerable, the exact extraction routine affected, or the specific paths that can be abused.

Exploitation Scenarios

No public PoC or exploit code is available for CVE-2026-77697. The attack chain described below is inferred from the vulnerability class (CWE-269, privilege escalation during JAR extraction) and the surrounding context of the ManageEngine Endpoint Central platform.

Step 1: Reconnaissance / Target Identification An attacker with local access to a server or endpoint running ManageEngine Endpoint Central (versions below 11.4.2540.23) begins by identifying the service account privileges under which the Endpoint Central processes execute. The attacker may also enumerate the endpoints used by Endpoint Central to ingest JAR files — such as update directories, patch staging areas, or plugin upload locations — to identify where a malicious archive could be introduced. File system inspection, checking where service binaries are located, and verifying the privileges granted to the Endpoint Central service account are typical reconnaissance activities.

Step 2: Triggering the Flaw The attacker crafts a malicious JAR archive designed to exploit weaknesses in the extraction routine. The JAR file may contain:

• Path traversal payloads to write outside the intended extraction directory (e.g., ../ traversal) into directories writable only by elevated privileges
• Replacement files for existing application components, configuration files, or scheduled job definitions
• Symlink or junction constructs that redirect writes performed during extraction to attacker-selected target paths

The malicious JAR must be introduced into a location where the Endpoint Central application will process it. This could be through an authenticated but low-privilege management interface (if one exists), direct file drop into an accessible staging folder, or manipulation of a pending update/patch queue.

Step 3: Payload / Execution When the Endpoint Central service processes the crafted JAR file during extraction — triggered by an update cycle, plugin load, or scheduled maintenance operation — the flawed extraction logic executs file operations in the security context of the service account. If the service runs as SYSTEM or another highly privileged account, the attacker's file writes succeed at that elevated level. The result may be:

• Overwriting a JAR file, library, or executable that the service subsequently loads, enabling code execution in the service's context
• Placing a new scheduled task or startup script that executes on the next service restart
• Modifying configuration data that induces the service to spawn processes under attacker control

Step 4: Post-Exploitation With file write capability at the service account privilege level, the attacker achieves code execution under that context. Depending on the Endpoint Central service account configuration (often SYSTEM or a privileged domain account in enterprise deployments), the attacker may:

• Extract secrets or credentials stored by the Endpoint Central service (notably device management passwords, domain credentials used for endpoint management, or agent authentication tokens)
• Install persistence mechanisms
• Lateral movement opportunities using compromised credentials to reach managed endpoints across the enterprise

No public PoC available; attack chain is inferred from vulnerability class.

Impact Assessment

From a business perspective, CVE-2026-77697 affects any organization running ManageEngine Endpoint Central below version 11.4.2540.23. Endpoint Central is a centralized management platform used to patch, configure, and administer endpoints across an enterprise, meaning the service account commonly holds broad rights: local SYSTEM privileges on the management server and domain-level credentials for communicating with and managing endpoints.

The CVSS subscores provide context on the severity envelope:

• Attack Vector: Local — exploitation requires local access to the vulnerable host; remote-only attackers need an initial foothold
• Attack Complexity: Low — no special conditions or timing windows required
• Privileges Required: Low — standard unprivileged user account suffices
• User Interaction: None — no victim action needed for exploitation
• Scope: Changed — the vulnerability can impact components beyond the vulnerable application
• Confidentiality, Integrity, Availability: Low — each is partially compromised

The blast radius is primarily the Endpoint Central management server itself. A successful exploit results in privilege escalation from a low-privilege local user to the service account context. Because Endpoint Central also stores credentials used to manage endpoints across the organization, a compromise of the server can cascade into broader network compromise — the domain/machine credentials cached on the server are high-value targets that could enable lateral movement across managed fleets. The availability impact could also affect the endpoint management operations if the service files are corrupted or if the service account is used for destructive actions.

Detection Guidance

Sigma Rule

title: Suspicious JAR Extraction by ManageEngine Endpoint Central
id: 6041b1ea-3725-4b3e-8a1d-c7f2e1a9b3d4
status: experimental
description: Detects anomalous file writes originating from ManageEngine Endpoint Central processes, potentially indicating exploitation of privilege escalation during JAR extraction.
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2026-77697
author: Valtersit Threat Intelligence
date: 2026/01/15
tags:
    - attack.privilege_escalation
    - attack.t1068
    - cve.2026.77697
logsource:
    category: file_event
    product: windows
detection:
    selection_process:
        Image|endswith:
            - '\java.exe'
            - '\ManageEngine\EndpointCentral\bin\wrapper.exe'
    selection_jar:
        TargetFilename|contains:
            - 'jar'
            - '\AppData\Local\Temp\'
        TargetFilename|endswith:
            - '.class'
            - '.jar'
            - '.exe'
            - '.dll'
            - '.jsp'
            - '.config'
    selection_highpriv_path:
        TargetFilename|contains:
            - '\Windows\System32\'
            - '\Program Files\'
            - '\ProgramData\'
            - '\EndpointCentral\bin\'
    condition:
        selection_process and selection_jar and selection_highpriv_path
falsepositives:
    - Legitimate software updates triggered by administrators
    - Normal plugin or hotfix installations
level: medium

YARA Rule

rule CVE_2026_77697_ManageEngine_JAR_Extraction_PrivEsc
{
    meta:
        author = "Valtersit Threat Intelligence"
        description = "Detects suspicious JAR files with path traversal or privilege escalation indicators targeting ManageEngine Endpoint Central"
        date = "2026-01-15"
        cve = "CVE-2026-77697"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-77697"
        severity = "medium"

    strings:
        $manifest = "META-INF/MANIFEST.MF"
        $path_traversal1 = "../" ascii
        $path_traversal2 = "..\\" ascii
        $path_traversal3 = "%2e%2e%2f" ascii
        $path_traversal4 = "%2e%2e%5c" ascii
        $windows_sys = "Windows/System32" ascii nocase
        $windows_sys2 = "Windows\\System32" ascii nocase
        $program_files = "Program Files" ascii nocase
        $program_data = "ProgramData" ascii nocase
        $java_class = ".class" ascii
        $endpoint_refs = ["endpoint" ascii nocase, "zentral" ascii nocase, "manageengine" ascii nocase]
        $service_dll = "service.dll" ascii nocase
        $config_ovr = ".config" ascii nocase

    condition:
        uint32be(0) == 0x504B0304 and  // PK\x03\x04 ZIP magic
        2 of ($path_traversal*) and
        any of ($endpoint_refs) and
        ($windows_sys or $windows_sys2 or $program_files or $program_data or $service_dll or $config_ovr)
}

Suricata IDS Rule

Proximity note: This vulnerability is local in nature. The signature below detects network-borne JAR deliveries that may be precursors to exploitation — such as when an attacker uploads a crafted package to a ManageEngine staging/upload endpoint prior to triggering the flawed extraction routine.

alert http any any -> $HOME_NET any (msg:"CVE-2026-77697 Possible ManageEngine Endpoint Central JAR Upload with Path Traversal Indicators"; flow:established,to_server; content:"POST"; http_method; content:".jar"; http_uri; nocase; content:"Content-Disposition"; http_header; nocase; pcre:"/filename=[^\\r\\n]*\\.jar/i"; pcre:"/\.\.([\\/\\\\]|%2e%2e[\\/\\\\])/i"; classtype:attempted-admin; reference:cve,2026-77697; sid:202677697; rev:1;)

Elastic Detection

The following EQL rule detects file write events from a Java process targeting privileged directories with a JAR or class extension — a signature of abused JAR extraction.

sequence by host.id, process.entity_id with maxspan=2m
  [file where event.action == "creation" and
      process.name == "java.exe" and
      file.name : ("*.jar", "*.class", "*.exe", "*.dll") and
      file.path : ("C:\\Windows\\System32\\*", "C:\\Program Files\\*", "C:\\ProgramData\\*")
  ]
  [file where event.action == "creation" and
      process.name == "java.exe" and
      file.path : ("*\\Temp\\*", "*\\EndpointCentral*") and
      file.extension : ("*.jsp", "*.class", "*.jar")
  ]

Splunk SPL Query

index=windows sourcetype="WinEventLog:Security" OR sourcetype="xmlwineventlog" EventCode=4688 OR EventCode=11
| rex field=CommandLine "(?<executable>\.*[\\/][^\\/\s]+$)"
| search (Image="*java.exe" OR Image="*wrapper.exe") (CommandLine="*jar*" OR CommandLine="*EndpointCentral*")
| rex field=TargetFilename "(?<written_path>(?i:C:[\\\][^\s]+))"
| where match(written_path, "(?i)(system32|program files|programdata|endpointcentral.bin)")
  AND (lower(written_path) LIKE "%jar%" OR lower(written_path) LIKE "%.class%" OR lower(written_path) LIKE "%.exe%" OR lower(written_path) LIKE "%.dll%")
| table _time, host, user, Image, CommandLine, written_path
| sort - _time

Wazuh OSSEC Rule

<group name="manageengine_cve_2026_77697,">
    <rule id="100977697" level="12">
        <if_sid>550, 620</if_sid>
        <field name="win.event.system.eventID">^11$</field>
        <description>CVE-2026-77697 - Suspected ManageEngine Endpoint Central JAR extraction writing to privileged directory</description>
        <match>jar|\.class|\.dll|\.exe|\.jsp</match>
        <regex>(?i)(system32|program files|programdata|endpointcentral.bin)</regex>
        <field name="win.event.data.image">(?i)(java|wrapper)</field>
        <group>privilege_escalation,pci_dss_6.5,gdpr_IV_35.7.d,</group>
        <mitre>
            <id>T1068</id>
        </mitre>
        <mitre>
            <id>T1068</id>
        </mitre>
    </rule>
</group>

Mitigation & Patch Guidance

Patch Confidence: 0/4 — UNPATCHED. No patch evidence from any tracked source exists at the time of this report. The fixed version (11.4.2540.23) has been referenced only in the NVD description itself and no official Zohocorp security advisory confirming a patch release has been identified.

1. Immediate mitigations:

   • Restrict local access to systems running ManageEngine Endpoint Central. Only grant interactive logon rights to trusted administrators. Since the attack requires local access (AV:L), reducing the number of local users directly shrinks the attack surface.
   • Enforce least-privilege service accounts. If Endpoint Central is running under a domain administrator or SYSTEM account, evaluate whether the service can operate under a reduced-privilege dedicated service account while still meeting functional requirements. This reduces the impact of a successful privilege escalation.
   • Monitor and restrict the directories and locations where JAR files can be dropped or staged on the Endpoint Central server. If possible, employ file integrity monitoring (FIM) on the Endpoint Central installation and configuration directories to alert on unexpected file modification or creation.
   • Harden the underlying operating system with local security policy — e.g., User Account Control (UAC) at maximum, Credential Guard enabled, and AppLocker or WDAC policies restricting which processes can execute from writable directories.

2. Patch/upgrade steps:

   • Upgrade ManageEngine Endpoint Central to version 11.4.2540.23 or later as soon as a vendor-verified build is available from Zohocorp.
   • Do not rely solely on the version number in the NVD description; independently verify the availability of version 11.4.2540.23 or a subsequent version from the official ManageEngine download portal or Zoho update channel.
   • Before upgrading, review Zohocorp's release notes and security advisories for any corroborating evidence that the fix addresses this vulnerability.

3. Long-term hardening:

   • Treat the Endpoint Central management server as a Tier-0/privileged asset. Segregate it from general-user workstations and restrict administrative access through a jump-host or privileged access management (PAM) solution.
   • Continuously monitor threat intelligence feeds and Zohocorp advisories for any updates on CVE-2026-77697, including potential inclusion in CISA KEV or active exploitation reports.
   • Apply a systematic vulnerability management program for all ManageEngine products, since Zoho's portfolio has been a repeated target for APT and ransomware groups historically (e.g., CVE-2021-40539 in ManageEngine ADSelfService Plus being exploited in the wild).
   • Collect and forward security-relevant logs (file write events, process creation, service account activity) from the Endpoint Central server to a centralized SIEM for forensic readiness.

References

1. National Vulnerability Database — CVE-2026-77697 — https://nvd.nist.gov/vuln/detail/CVE-2026-77697 (Primary source of the vulnerability description and CVSS vector for this report.)
2. Zohocorp ManageEngine Endpoint Central Official Site — https://www.manageengine.com/products/desktop-central/ (For validating patched version availability and release notes.)
3. FIRST.org EPSS — https://www.first.org/epss/ (Monitoring for EPSS score once assigned; score is pending as of this report.)
4. CISA Known Exploited Vulnerabilities Catalog — https://www.cisa.gov/known-exploited-vulnerabilities-catalog (Currently lists CVE-2026-77697 as NO; monitor for inclusion if exploitation evidence emerges.)
5. MITRE ATT&CK — T1068 — Exploitation for Privilege Escalation — https://attack.mitre.org/techniques/T1068/ (Contextual framework for detection engineering and threat modeling.)

Known threat actor campaigns / in-the-wild exploitation: No public evidence of active exploitation, exploit code, or threat actor campaigns targeting CVE-2026-77697 exists as of this report. The same vendor product family (ManageEngine Endpoint Central/Desktop Central) has prior notable vulnerabilities that were exploited in the wild (e.g., CVE-2021-40539), underscoring the strategic importance of this product to attackers when targeting enterprise environments. Enterprises must assume that exploit development is likely given the low complexity and local privilege requirement.