CVE-2010-0249 Microsoft CVE debrief

Who should care

Security and endpoint teams, vulnerability management owners, and administrators responsible for environments where Internet Explorer is still present or accessible.

Technical summary

The supplied corpus identifies the issue as a use-after-free vulnerability in Microsoft Internet Explorer and places it in CISA’s Known Exploited Vulnerabilities catalog. Beyond that, the source set does not provide version ranges, attack preconditions, or patch specifics. The defensible takeaway is that CISA considers the issue actively exploited enough to require prompt mitigation or removal of exposure.

Defensive priority

High priority. KEV listing status means remediation should be treated as urgent, with attention to the supplied due date of 2026-06-03.

Recommended defensive actions

• Confirm whether Internet Explorer is installed, enabled, or reachable in your environment.
• Apply Microsoft vendor mitigations referenced by the official advisory and related guidance.
• If mitigations are unavailable or insufficient, discontinue use of Internet Explorer where possible.
• Follow applicable BOD 22-01 guidance for cloud services if the affected product is used there.
• Track remediation against the supplied KEV due date of 2026-06-03.
• Validate exposure using asset inventory and endpoint configuration checks.

Evidence notes

This debrief is based only on the supplied KEV metadata and the official record links provided in the corpus. The source item states Microsoft Internet Explorer use-after-free vulnerability, marks it as KEV-listed, and instructs defenders to apply vendor mitigations or discontinue use if mitigations are unavailable. No additional exploitation, version, or patch details were included in the supplied corpus.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.