Threats / Microsoft / CVE-2015-1641
CVE-2015-1641
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-08-04
Microsoft Office vulnerability
Microsoft Office memory corruption vulnerability in rich text format handling enables remote code execution with user privileges. High exploitation activity observed in the wild.
Verdict
Today item — known-exploited.
A memory corruption flaw in Office's RTF processing allows attackers to achieve code execution by crafting malicious documents. The high EPSS score and active exploitation indicate significant real-world risk despite no CVSS assignment.
CISA KEV Yes · 2021-11-034EPSS 0.92939 (verify live)5CVSS 7.8 (CISA)3CISA SSVC Exploitation: active · Automatable: no · Impact: total3
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
25 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03).
Probability (EPSS)
EPSS 0.92939 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 7.8 (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) · Affected: Microsoft, Office. Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
Weakness (CWE)
Mapped to CWE-399 Resource Management Errors — weakness family: Resource / availability.CWE assignment from the public NVD record (may be stale); the weakness class drives how the flaw is exploited.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog 2395 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious rich text format file that triggers memory corruption when opened in Microsoft Office.
Business
Users receive weaponized documents via email or file sharing, creating widespread infection vectors across the organization.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I deliver the malicious RTF file to target users through social engineering or watering hole tactics.
Business
Attackers gain execution context matching the compromised user's privileges, enabling lateral movement and data exfiltration.
3
Lateral reach — past segmentation narrative 3
Attacker
I execute arbitrary code within the Office process to establish persistence or deploy secondary payloads.
Business
Incident response costs, system remediation, and potential regulatory notification obligations materialize from confirmed compromise.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05