Yes. CISA added CVE-2015-0071 to its Known Exploited Vulnerabilities catalogue on 25 May 2022, which it does only when there is reliable evidence of active exploitation. CISA has not linked it to known ransomware campaigns. Microsoft Internet Explorer allows remote attackers to bypass the address space layout randomization (ASLR) protection mechanism via a crafted web site.
What this means for exploitation status
When a CVE is in CISA’s Known Exploited Vulnerabilities catalogue, the practical question is no longer whether exploitation is plausible but whether the environment is still exposed. For an Internet Explorer issue like this, that means treating any remaining use of the affected browser path as an active risk condition and checking whether the vulnerability path can still be reached through legacy endpoints, embedded browser controls, or compatibility dependencies.
Because the vulnerability is an ASLR bypass rather than a standalone code execution bug, it matters most as an enabler. It can lower the cost of a broader exploit chain by weakening a core platform defence, so the immediate priority is to understand whether Internet Explorer is still installed, invoked, or indirectly available in the environment, even if users believe it is no longer their primary browser.
How to confirm exposure and reduce the attack path
Start by identifying where Internet Explorer remains enabled, callable, or required for business workflows. That includes older line-of-business applications, web portals that depend on IE compatibility mode, and systems that still allow the browser binary to launch. If those paths exist, the practical exposure is not theoretical, because attackers only need one reachable entry point to benefit from the bypass.
- Inventory any hosts where Internet Explorer components are still present or permitted.
- Check whether users or applications can still open untrusted web content through that path.
- Confirm whether compensating browser hardening and attack surface reduction settings are in place.
- Remove or disable legacy browser access where the business does not truly require it.
For a broader view of how browser exposure fits into an exploitation chain, see the Enterprise Browser and Browser Security Guide, which is useful when the issue is not just one CVE but the persistence of risky browser pathways.
What to do if patching or removal must wait
If immediate remediation is not possible, reduce the chances that the browser path can be used to deliver or stage a follow-on exploit. The most effective short-term move is to narrow where Internet Explorer can be launched and to restrict access to untrusted websites, especially on systems that already carry elevated privileges or access to sensitive internal applications.
Use the CISA KEV catalogue as the prioritization signal, then validate the vendor advisory for the exact remediation path on your platform. In parallel, confirm whether endpoint controls, web filtering, and application allowlisting are strong enough to make the legacy path non-routine rather than merely “still installed.”
For prioritisation discipline, the Zero-Day and Exploited Vulnerabilities Guide is the most relevant internal reference when you need to decide how aggressively to treat a KEV-listed issue before normal patch cycles catch up.
Risk and Threat Considerations
The main risk is exploit chaining. An ASLR bypass can make other browser or script-based exploitation more reliable, which means the practical danger is not just the CVE itself but the way it supports broader compromise of a user session or endpoint. Systems that still trust legacy browser execution paths also create a durable exposure surface that defenders may overlook.
Failure mechanism: An attacker delivers crafted web content to a system that still exposes the vulnerable Internet Explorer code path, uses the ASLR bypass to weaken memory-layout uncertainty, and then combines that advantage with another flaw or malicious payload to increase exploit reliability.
Impact: Successful exploitation can enable deeper endpoint compromise, user session abuse, or lateral movement opportunities if the affected machine has network reach or access to sensitive internal resources.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
CIS Controls v8, NIST CSF 2.0 and NIST SP 800-53 Rev 5 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| CIS Controls v8 | CIS-7 — Continuous Vulnerability Management | KEV-listed exploitation requires prioritised vulnerability handling and exposure validation. |
| Recommendation — Prioritize and remediate KEV-listed exposure paths before routine backlog items. | ||
| NIST CSF 2.0 | ID.RA-01 — Asset Vulnerabilities Are Identified and Documented | The question turns on confirming whether vulnerable browser exposure still exists. |
| PR.PS-04 — Platform Software Is Patched | Active exploitation makes timely remediation and patch hygiene central to the answer. | |
| Recommendation — Document where the vulnerable browser path remains reachable and executable. Patch or remove the exposed browser components as soon as validated remediation is available. | ||
| NIST SP 800-53 Rev 5 | SI-2 — Flaw Remediation | Actively exploited vulnerabilities require rapid remediation and exception handling. |
| SI-4 — System Monitoring | Checking for earlier compromise requires monitoring and investigation of suspicious browser use. | |
| Recommendation — Track, remediate, and verify closure of the exploited browser flaw. Monitor for signs that the vulnerable browser path was used in an intrusion chain. | ||
Practitioner Guidance
What to verify: Confirm whether Internet Explorer is actually disabled in practice, not just deprecated on paper. A system is still exposed if users can invoke the browser, if compatibility settings silently re-enable it, or if enterprise applications depend on it for authenticated workflows.
Decision rule: If the host can reach the internet or trusted internal web apps through Internet Explorer, treat this as a priority remediation item and do not rely on “low likelihood” arguments simply because the browser is old. For KEV-listed issues, exposure and reachability matter more than theoretical rarity.
Practitioner takeaway: The right response is to remove or constrain the legacy browser path first, then verify whether the system was ever used as an initial access point or exploit staging point before assuming the issue is only historical.
Related resources from NHI Mgmt Group
- CVE-2015-0071 (Microsoft Internet Explorer ASLR Bypass)
- Is CVE-2010-3962 (Microsoft Internet Explorer Uninitialized Memory Corruption) being exploited in the wild?
- Is CVE-2012-4792 (Microsoft Internet Explorer Use-After-Free) being exploited in the wild?
- Is CVE-2013-3163 (Microsoft Internet Explorer Memory Corruption) being exploited in the wild?
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Reviewed and updated by the NHIMG editorial team on October 19, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org