1. Introduction
A Adobe Flash file has been detected on a url, indicating a potential security risk. Flash is an outdated technology and will reach End Of Life (EOL) on December 31, 2020. This poses a risk to confidentiality, integrity, and availability as unpatched vulnerabilities in Flash could be exploited by attackers. Systems running Adobe Flash Player are usually affected.
2. Technical Explanation
The vulnerability stems from the use of an unsupported technology – Adobe Flash Player – which is no longer receiving security updates. Attackers can exploit known vulnerabilities within Flash to execute malicious code on vulnerable systems. The primary risk is remote exploitation, meaning attackers do not need local access to compromise a system.
- Root cause: Adobe Flash Player has reached End Of Life and will no longer receive security patches.
- Exploit mechanism: Attackers can deliver malicious payloads through crafted Flash content that exploits known vulnerabilities in the player.
- Scope: Systems running any version of Adobe Flash Player are affected, especially those unable to be updated or removed.
3. Detection and Assessment
To confirm if a system is vulnerable, check for the presence of Adobe Flash Player components. A quick check involves reviewing installed applications. A thorough method includes scanning for Flash-related files and registry entries.
- Quick checks: Check the list of installed programs in Windows Control Panel or use the command
about:pluginsin Chrome to see if Flash is listed. - Scanning: Nessus plugin ID 139254 can detect Adobe Flash Player installations. This is an example only.
- Logs and evidence: Check for Flash-related entries in application event logs, though these are unlikely to directly indicate vulnerability status.
about:plugins4. Solution / Remediation Steps
The primary solution is to remove Adobe Flash Player from affected systems. This eliminates the risk of exploitation due to known vulnerabilities in the software.
4.1 Preparation
- There are no dependencies to consider. Roll back involves reinstalling Adobe Flash Player if needed (though this is strongly discouraged).
- Change windows are unlikely to be needed unless part of a wider software update cycle. Approval may not be required for removing outdated software.
4.2 Implementation
- Step 1: Uninstall Adobe Flash Player through the Windows Control Panel or Settings app.
- Step 2: Verify that all Flash components have been removed by checking the list of installed programs again.
4.3 Config or Code Example
Before
Adobe Flash Player 32.0.0.371 (Installed)After
(No Adobe Flash Player entries found in installed programs list)4.4 Security Practices Relevant to This Vulnerability
- Practice 1: Maintain a current software inventory to identify outdated or unsupported applications like Flash Player.
- Practice 2: Implement a regular patch management cycle to ensure all supported software is up-to-date with the latest security fixes.
4.5 Automation (Optional)
PowerShell can be used to uninstall Adobe Flash Player at scale. Use caution when running scripts in automated environments.
# Example PowerShell script (use with caution!)
Get-WmiObject -Class Win32_Product | Where-Object {$_.Name -like "*Adobe Flash*"} | Uninstall-Product -Confirm:$false5. Verification / Validation
Verify the fix by confirming Adobe Flash Player is no longer present on the system and re-running detection methods used earlier. A simple service smoke test involves browsing websites that previously required Flash to ensure functionality isn’t broken (though this should not be expected).
- Post-fix check: Run
about:pluginsin Chrome; no Adobe Flash Player entry should be present. - Re-test: Check the list of installed programs again; Adobe Flash Player should not appear.
- Smoke test: Verify that core system functions and other applications are working as expected.
- Monitoring: Monitor application event logs for any errors related to missing Flash components (example only).
about:plugins6. Preventive Measures and Monitoring
Preventive measures include updating security baselines to exclude outdated software like Adobe Flash Player, implementing checks in CI/CD pipelines to prevent deployment of vulnerable applications, and establishing a regular patch review cycle for all supported software.
- Baselines: Update security baselines or policies to explicitly disallow the installation of Adobe Flash Player.
- Asset and patch process: Establish a regular review cycle (e.g., monthly) to identify and remove outdated software from systems.
7. Risks, Side Effects, and Roll Back
Removing Adobe Flash Player may break functionality on older websites that still require it. However, this is generally considered an acceptable risk given the security implications of running unsupported software. Roll back involves reinstalling Adobe Flash Player (strongly discouraged).
- Risk or side effect 2: Users may experience compatibility issues with older content that relies on Flash.
- Roll back: Step 1: Reinstall Adobe Flash Player from the official Adobe website (not recommended).
8. References and Resources
- Vendor advisory or bulletin: https://www.adobe.com/products/flashplayer/end-of-life.html
- NVD or CVE entry: Not applicable, as this is an EOL issue rather than a specific vulnerability.
- Product or platform documentation relevant to the fix: https://helpx.adobe.com/flash-player/kb/uninstall-flash-player.html