CVE-2018-15982: Adobe Flash Player Use-After-Free Vulnerability

CVE-2018-15982 is a use-after-free vulnerability in Adobe Flash Player, specifically involving the com.adobe.tvsdk.mediacore.metadata component. It allows an attacker to trigger memory corruption that can lead to arbitrary code execution in the context of the Flash Player process. This matters because Flash Player was widely embedded in browsers and applications, the flaw has been tied to ransomware activity, and the product is end-of-life, leaving any remaining installations without ongoing vendor support.

Defenders still encountering Flash content or legacy systems that load it should treat this as a high-priority risk and confirm all details against the vendor advisory and CISA guidance.

How it works

The vulnerability is classified as CWE-416 (Use-After-Free). In this class of flaw, the software frees a block of memory but later continues to reference it. An attacker who can influence the allocation and freeing of objects around the affected media-core metadata handling can arrange for that dangling reference to point to attacker-controlled data.

When the dangling pointer is subsequently used, the process may execute unintended code or corrupt its own state. In the Flash Player environment this typically occurs when a user opens a malicious SWF or visits a page that loads crafted Flash content. Exact trigger conditions and exploitation mechanics must be confirmed against the vendor advisory; public detail beyond the component name and CWE is limited here.

Am I affected? How to find it in your systems

Adobe Flash Player historically ran as a browser plug-in (Internet Explorer, Edge legacy, Chrome, Firefox, Safari) and as a stand-alone projector or embedded ActiveX/NPAPI component inside desktop applications and enterprise kiosks. It may still appear on older Windows, macOS, or Linux images, thin-client environments, or industrial systems that never completed the Flash removal effort.

• Inventory endpoints and servers for any remaining Flash Player binaries, browser plug-in registries, or references to flash*.ocx / libflashplayer.so.
• Check installed version strings against the list of affected builds published in the vendor advisory; do not rely on generic “Flash is gone” assumptions.
• Scan software bills of materials, application whitelists, and package inventories for Adobe Flash or tvsdk-related libraries.
• Review web proxy, browser, and endpoint logs for attempts to load .swf files or for crashes in the Flash process that coincide with suspicious network activity.
• On Windows, examine Add/Remove Programs, the Flash Player Install Manager, and Prefetch/Amcache entries; on other platforms use package managers and file-system searches.

Any system still capable of executing Flash content should be treated as potentially affected until proven otherwise.

How to remediate

The primary remediation is to apply the vendor update that addresses CVE-2018-15982, confirming the exact fixed build from the official Adobe advisory. Because Adobe Flash Player is end-of-life, CISA’s required action is to disconnect the impacted product if it is still in use.

• Remove Flash Player completely from all managed endpoints using the official uninstaller and verify residual files and registry keys are gone.
• Block Flash MIME types and file extensions at web proxies and email gateways.
• Disable or uninstall any browser plug-in or ActiveX control that can invoke Flash.
• Replace or rewrite any internal applications that still depend on Flash content.
• Enforce application-allow-listing so that flashplayer.exe or equivalent binaries cannot launch.

After removal, re-scan to confirm the component is absent and update asset inventories accordingly.

If you can't patch immediately

If immediate removal is operationally impossible, apply compensating controls while planning full disconnection:

• Network-segment any host that still requires Flash so it cannot reach the open internet or high-value internal assets.
• Use a web application firewall or reverse-proxy rule set to drop or sanitize requests that attempt to serve Flash content.
• Disable the affected feature or component wherever the application configuration allows it.
• Increase monitoring: alert on Flash process creation, unexpected .swf downloads, and memory-corruption crash signatures.
• Apply strict least-privilege policies and ensure the Flash process runs with minimal rights if it must remain temporarily.
• Virtual-patch signatures from endpoint-protection or IPS vendors may provide short-term coverage; validate them against the vendor advisory.

These measures only reduce risk; they do not replace the CISA direction to disconnect the end-of-life product.

If your data may have been exposed

Actively exploited vulnerabilities, especially those with known ransomware use, frequently lead to broader compromise and data theft. If you have evidence of exploitation or if Flash Player remained accessible on systems that handle sensitive information, initiate incident-response procedures, preserve relevant logs, and assess whether credentials or data left the environment. You can run a free exposure scan of your email addresses against known breach data sets to determine whether associated accounts appear in prior leaks and then force password resets and enable multi-factor authentication where needed.