CVE-2014-0322 is an use-after-free vulnerability in Microsoft Internet Explorer. CISA added it to the Known Exploited Vulnerabilities catalogue on 4 May 2022, which means attackers have used it in real attacks. Use-after-free vulnerability in Microsoft Internet Explorer allows remote attackers to execute code.
How this vulnerability class works
Use-after-free flaws happen when software continues to use memory after it has been released, which can corrupt program state and let an attacker influence control flow. In a browser like Internet Explorer, that kind of memory safety failure is especially dangerous because a crafted webpage or script can trigger it remotely and turn a simple browsing action into code execution.
The important security point is that the bug is in the browser engine, not just in a single page or add-on. That means the attack surface is broad wherever the vulnerable rendering or scripting path is reachable, and exploitation can occur before a user notices anything unusual.
Why this is dangerous in Internet Explorer
Browser memory corruption flaws are high value to attackers because they can deliver initial code execution with little or no user interaction beyond visiting a malicious page. Once the browser process is compromised, attackers may be able to run payloads in the context of the current user, stage additional malware, or chain the exploit with privilege escalation or persistence techniques.
For older browser platforms, danger is amplified by legacy compatibility modes, embedded enterprise dependencies, and environments where the browser remains enabled for specific internal applications. A vulnerability like this is not just a browser crash risk, it is a possible entry point into the endpoint and, from there, the wider network.
How organisations assess exposure and reduce it
Exposure review starts with knowing where the affected browser is still installed, enabled, or required for business workflows. Organisations should check endpoint inventory, browser usage data, and vendor guidance, then compare those systems against the NIST National Vulnerability Database and the CVE Program record for authoritative vulnerability identification.
Where patching is delayed, compensating controls matter: restrict internet exposure, reduce or disable legacy browser use, limit scripting and plug-in execution where feasible, and isolate higher-risk browsing into hardened or segregated environments. For prioritisation and remediation workflow, the Vulnerability Management Guide is useful for organising scope, verification, and exception handling around actively exploited issues.
Detection, compromise review, and post-exploitation impact
Because this is a known exploited vulnerability, detection should focus on signs that the browser was used as an initial access vector, not only on whether the crash itself was observed. Look for suspicious browser launches, unexpected child processes, downloaded payloads, unusual script activity, and lateral movement that follows a browsing event.
If exploitation is suspected, review the endpoint for dropped files, persistence mechanisms, tampered browser settings, and credential theft indicators. Browser-based exploitation can expose session material, tokens, stored credentials, or access to internal applications, so post-incident review should include identity and session impact as well as malware containment.
Risk and Threat Considerations
This vulnerability is dangerous because it combines remote reach with a trustworthy user action, namely opening a web page. Attackers favour browser memory corruption flaws because they can deliver code execution early in the intrusion chain and use the browser as a foothold for follow-on abuse.
Failure mechanism: The use-after-free condition can be manipulated to corrupt memory, steer execution, or crash the process in a way that reveals exploitable control over the browser.
Impact: Successful exploitation can give an attacker initial code execution, lead to malware deployment, and create a path to credential theft or further compromise of the endpoint and connected services.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
NIST SP 800-53 Rev 5 and CIS Controls v8 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST SP 800-53 Rev 5 | SI-2 — Flaw Remediation | Tracks remediation of known software flaws like exploited browser vulnerabilities |
| RA-5 — Vulnerability Monitoring and Scanning | Supports discovering where the vulnerable browser is deployed and exposed | |
| SC-18 — Mobile Code | Helps govern browser-executed active content that can trigger web-delivered exploitation | |
| Recommendation — Prioritise SI-2 remediation for exposed endpoints and verify patch status after deployment. Use RA-5 to locate affected systems and validate exposure before remediation. Apply SC-18 restrictions to reduce risky active content execution in browser contexts. | ||
| CIS Controls v8 | CIS-7 — Continuous Vulnerability Management | Directly addresses prioritising and remediating known exploited vulnerabilities |
| CIS-10 — Malware Defenses | Supports detecting and containing payloads delivered after browser exploitation | |
| Recommendation — Use CIS-7 to identify, prioritise, and remediate the vulnerable browser estate quickly. Use CIS-10 to detect, block, and contain malware introduced through exploitation. | ||
Practitioner Guidance
Why practitioners should care: Treat actively exploited browser vulnerabilities as exposure management issues, not routine patch tickets. If the browser is still part of the operational stack, the organisation needs a clear owner for inventory, mitigation, and retirement decisions.
What to watch for: Prioritise systems that still rely on legacy browser behaviour, especially endpoints that reach untrusted websites or internal users who cannot easily move off the affected browser path. If patching cannot happen immediately, reduce exposure by narrowing where the browser can run and what it can load.
Practitioner takeaway: For browser RCE-class flaws, remediation is only complete when exposure, detection, and post-exploitation review have all been addressed, not just when the patch is installed.