{"basis":"claimed","id":"CVE-2018-0798","name":"Microsoft Office Memory Corruption Vulnerability","vendorProject":"Microsoft","product":"Office","publishedAt":"2018-01-10","cvss":{"score":8.8,"severity":"HIGH","version":"3.1"},"exploited":{"kevAdded":"2021-11-03","dueDate":"2022-05-03","ransomware":false},"epss":{"score":0.95121,"percentile":0.99863,"date":"2026-11-02"},"coverage":{"cloudflare":{"status":"no_history","firstOn":null,"daysToRule":null},"aws":{"status":"no_history","firstOn":null,"daysToRule":null},"azure":{"status":"none","firstOn":null,"daysToRule":null},"google":{"status":"no_history","firstOn":null,"daysToRule":null},"fastly":{"status":"no_history","firstOn":null,"daysToRule":null},"f5":{"status":"no_history","firstOn":null,"daysToRule":null},"akamai":{"status":"no_source","firstOn":null,"daysToRule":null},"crs":{"status":"no_history","firstOn":null,"daysToRule":null}},"title":null,"description":"Equation Editor in Microsoft Office 2007, Microsoft Office 2010, Microsoft Office 2013, and Microsoft Office 2016 allows a remote code execution vulnerability due to the way objects are handled in memory, aka \"Microsoft Office Memory Corruption Vulnerability\".","cwes":["CWE-787"],"vendors":[{"vendor":"cloudflare","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"aws","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"azure","status":"none","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"google","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"fastly","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"f5","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"akamai","status":"no_source","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]},{"vendor":"crs","status":"no_history","basis":"claimed","firstOn":null,"firstIsNew":false,"daysToRule":null,"daysAtMost":null,"freePlan":false,"claims":[]}],"updatedAt":"2026-11-04T01:17:43.972Z","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","ssvc":{"exploitation":"active","automatable":"no","technicalImpact":"total"},"kevAction":"Apply updates per vendor instructions.","kevNotes":"https://nvd.nist.gov/vuln/detail/CVE-2018-0798","references":[{"url":"http://www.securityfocus.com/bid/102370","name":"102370","tags":["vdb-entry","x_refsource_BID"]},{"url":"http://www.securitytracker.com/id/1040153","name":"1040153","tags":["vdb-entry","x_refsource_SECTRACK"]},{"url":"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-0798","name":null,"tags":["x_refsource_CONFIRM"]},{"url":"https://0patch.blogspot.com/2018/01/bringing-abandoned-equation-editor-back.html","name":null,"tags":["x_refsource_MISC"]}],"affected":[{"vendor":"Microsoft Corporation","product":"Equation Editor","affected":["Microsoft Office 2007, Microsoft Office 2010, Microsoft Office 2013, and Microsoft Office 2016"],"fixed":[]}],"briefing":{"status":{"id":"known_exploited","label":"Known exploited"},"why":"CISA lists CVE-2018-0798 as exploited in the wild since 2021-11-03. It is reachable over the network without credentials (CVSS 8.8). No edge WAF vendor names it in a changelog, so default managed rules may or may not catch it.","who":"Teams running Microsoft Corporation Equation Editor (Microsoft Office 2007, Microsoft Office 2010, Microsoft Office 2013, and Microsoft Office 2016). Prioritise internet-facing instances.","what_to_do":[{"text":"Apply the vendor's fix; the advisory lists the affected and fixed versions."},{"text":"CISA's required action: Apply updates per vendor instructions. US federal agencies must act by 2022-05-03."},{"text":"Review exposed instances for signs of compromise: it was exploited before many systems were patched, and a later patch does not undo access already gained."},{"text":"Do not rely on WAF defaults: no edge vendor names this CVE. Restrict access to the vulnerable component or add a custom rule until it is patched.","href":"#edge","linkText":"Edge coverage"},{"text":"Check which WAF sits in front of your site and whether it covers this CVE.","href":"#check","linkText":"Check your domain"}],"evidence":[{"heading":"CVE record","text":"CVSS 3.1 8.8 (high). Weakness: CWE-787.","links":[{"label":"CVE-2018-0798","href":"https://www.cve.org/CVERecord?id=CVE-2018-0798"},{"label":"NVD","href":"https://nvd.nist.gov/vuln/detail/CVE-2018-0798"}]},{"heading":"Exploit evidence","text":"No public exploit code found in Exploit-DB, Metasploit, nuclei-templates or GitHub. That does not mean none exists.","links":[]},{"heading":"CISA KEV","text":"Added 2021-11-03, federal due date 2022-05-03 (catalog 2026.11.03, checked 2026-11-04).","links":[{"label":"CISA KEV catalog","href":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2018-0798"}]},{"heading":"EPSS","text":"95.1% probability of exploitation activity in the next 30 days, higher than 99% of CVEs (2026-11-02).","links":[{"label":"FIRST EPSS","href":"https://api.first.org/data/v1/epss?cve=CVE-2018-0798"}]},{"heading":"WAF vendor statements","text":"No edge vendor changelog names it.","links":[]}],"agent_prompt":"Assess whether the infrastructure available to you is affected by CVE-2018-0798 (Microsoft Office Memory Corruption Vulnerability). Perform a read-only assessment within your authorized access. Do not send exploit traffic, scan third-party systems, change configuration or restart services.\n\n1. Verify the CVE record at https://www.cve.org/CVERecord?id=CVE-2018-0798 and the vendor advisory. Establish affected and fixed versions, including vendor backports. The record lists: Microsoft Corporation Equation Editor: affected Microsoft Office 2007, Microsoft Office 2010, Microsoft Office 2013, and Microsoft Office 2016. Cite sources and retrieval dates; flag anything you cannot verify.\n2. Inventory deployments of Microsoft Office: asset, environment, owner where known, installed version or build, and how you confirmed it (package metadata, a version endpoint, image tags). An image tag alone does not prove the running version.\n3. Identify which deployments are reachable from the internet or untrusted networks, and through which paths (direct origin, load balancer, CDN or WAF).\n4. Assess compensating controls separately from patch status. Current edge WAF coverage for this CVE: no edge WAF vendor names it. Live data: https://cve.vigilbase.com/api/v1/cves/CVE-2018-0798. Check whether the rule is enabled and in block mode on each path, and whether any path bypasses the WAF. A WAF rule is not a patch.\n5. It is known exploited (CISA KEV): review logs on exposed instances for signs of exploitation before and after patching.\n\nReturn a short summary and a table: asset | version/build | assessment (affected, fixed, not applicable, unknown) | exposure | compensating control | evidence | next action. List what you could not assess and the access needed to resolve it. Do not infer absence of compromise from patch status or a lack of alerts.\n\nRemediation guidance: Apply the vendor's fix; the advisory lists the affected and fixed versions. CISA's required action: Apply updates per vendor instructions. US federal agencies must act by 2022-05-03.\nMore: https://cve.vigilbase.com/cve/CVE-2018-0798"},"measured":[],"sightings":null,"social":{"total":0,"first_seen":null,"daily":[{"day":"2026-10-22","posts":0},{"day":"2026-10-23","posts":0},{"day":"2026-10-24","posts":0},{"day":"2026-10-25","posts":0},{"day":"2026-10-26","posts":0},{"day":"2026-10-27","posts":0},{"day":"2026-10-28","posts":0},{"day":"2026-10-29","posts":0},{"day":"2026-10-30","posts":0},{"day":"2026-10-31","posts":0},{"day":"2026-11-01","posts":0},{"day":"2026-11-02","posts":0},{"day":"2026-11-03","posts":0},{"day":"2026-11-04","posts":0}],"top_posts":[],"exploit_repositories":[]}}