CVE-2010-3333 is a stack-based buffer overflow vulnerability in Microsoft Office. CISA added it to the Known Exploited Vulnerabilities catalogue on 3 March 2022, which means attackers have used it in real attacks. A stack-based buffer overflow vulnerability exists in the parsing of RTF data in Microsoft Office and earlier allows an attacker to perform remote code execution.
What a stack-based buffer overflow means in Microsoft Office
This vulnerability class matters because Office parses untrusted document content, and a stack overflow can let malformed input overwrite control data in memory. In practice, that can turn a simple file-open action into code execution on the victim system.
In Microsoft Office, the danger is amplified by how widely Office documents are exchanged and previewed. A malicious RTF file can become an initial access path, especially when users trust the file source or when content is delivered through email or shared drives.
Why this kind of flaw is dangerous
Stack-based overflows are often treated as a memory-safety issue, but the security impact is broader: the attacker may be able to run arbitrary code in the context of the Office process and then pivot to the rest of the endpoint. That can expose files, cached credentials, and other sensitive data already reachable on the host.
Because the vulnerable code path is the parser, exploitation can occur before any meaningful user interaction beyond opening or rendering the document. That makes detection and user awareness less reliable than for attacks that require repeated prompts or obvious macros.
How organisations assess exposure and reduce attack surface
Exposure starts with asset inventory: organisations need to know where Microsoft Office is installed, which endpoints open externally sourced documents, and which mail and collaboration paths deliver RTF files. They should also review vendor advisories and the NIST National Vulnerability Database alongside the CVE Program record to confirm the affected product and authoritative vulnerability details.
When patching is delayed, compensating controls should focus on reducing exposure to untrusted Office documents, limiting risky preview and rendering paths, and tightening application control on endpoints that routinely handle external files. Vulnerability prioritisation should also treat this as a high-priority item because the CISA KEV listing shows it was observed in real-world attacks.
Detection, remediation, and post-exploitation review
Defenders should look for unusual Office process behaviour, child processes spawned from Office applications, crashes in document parsing, and suspicious follow-on activity after a document is opened. Because exploitation can lead to code execution, the incident review should include endpoint telemetry, mailbox or download provenance, and any evidence of lateral movement from the affected workstation.
After remediation, organisations should verify that the vulnerable file path is no longer reachable, confirm that exposed documents were not repeatedly opened, and review whether the attacker could have accessed tokens, cached sessions, or other locally available secrets. NHI Mgmt Group’s Vulnerability Management Guide is useful here because remediation should be validated, not merely applied, and CWE Top 25 Guide helps teams connect this flaw to the broader memory-safety weakness class.
Risk and Threat Considerations
Weaponised document parsing flaws are attractive because they blend into normal business workflow and can be delivered at scale through email or file-sharing channels. Once exploited, they can provide a foothold for ransomware, credential theft, or further exploitation on the endpoint.
Failure mechanism: The attacker supplies malformed RTF content that triggers a stack-based overflow during parsing, overwriting control flow and enabling code execution inside the Office process.
Impact: Successful exploitation can lead to endpoint compromise, document theft, credential exposure, and subsequent movement into other systems reachable from the infected host.
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-10 — Information Input Validation | RTF parsing safety depends on validating untrusted input before processing. |
| SI-16 — Memory Protection | Stack overflow exploitation is a memory-protection failure in application processing. | |
| RA-5 — Vulnerability Monitoring and Scanning | This CVE needs inventory and exposure tracking so affected Office systems are found quickly. | |
| Recommendation — Validate external document input before parsing to reduce memory corruption risk. Apply memory-protection controls to reduce overwrite and code-execution opportunities. Scan and track affected endpoints so remediation is prioritised and verified. | ||
| CIS Controls v8 | CIS-7 — Continuous Vulnerability Management | A KEV-listed Office CVE requires ongoing discovery, prioritisation, and verification. |
| CIS-10 — Malware Defenses | Document-based exploitation often leads to malicious code execution on endpoints. | |
| Recommendation — Continuously identify and remediate vulnerable Office installations. Harden endpoint malware defenses to help catch exploit payloads and post-exploit activity. | ||
Practitioner Guidance
Why practitioners should care: Treat this class of Office flaw as an exposure-management problem, not just a patching issue. Organisations often underestimate how much trust they place in document workflows, which makes vulnerable parsers a durable entry point for attackers.
What to watch for: Correlate user-reported document opens with process creation, crash events, and any unexpected outbound connections from Office-related processes. If the parser is being abused, the earliest signs are often subtle.
Practitioner takeaway: Prioritise remediation, then confirm the environment can still detect document-driven compromise rather than assuming the patch alone closed the risk.