CVE-2026-66302: Skype for Business Remote Code Execution Vulnerability
- Is it exploited?
Not on CISA's list. CISA has not added it to the Known Exploited Vulnerabilities catalog as of . If CISA adds it, this page shows it as known exploited.
- How likely is exploitation in the next 30 days?
- 1%
EPSS score, percentile 62 of all scored records. A probability estimated by FIRST, not a report of exploitation.
- How severe?
- 9.8 Critical
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA has set no required action, because the vulnerability is not in KEV.
- Which versions are affected?
Affected
- from 9319.0 to before 6.0.9319.885
- from 2046.0 to before 7.0.2046.569
- from 2046.0 to before 7.0.2046.879
Source: CISA KEV 2026.10.29, as of ; FIRST EPSS, as of ; CVE List, as of . About the data.
What to do
Advisories and patches
This summary is based on the CVE record as of . Check the vendor's advisory before you act: affected versions and fixes can change.
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from 9319.0 to before 6.0.9319.885 |
| Status | Versions |
|---|---|
| Affected | from 2046.0 to before 7.0.2046.569 |
| Status | Versions |
|---|---|
| Affected | from 2046.0 to before 7.0.2046.879 |
Source: CVE List, as of . About the data.
About this vulnerability
External control of file name or path in Skype for Business allows an unauthorized attacker to execute code over a network.
Summary: CVE record, as of .
- CISA has not added CVE-2026-66302 to its Known Exploited Vulnerabilities (KEV) catalog, as of 29 Oct 2026.
- The CVE record was published on 8 Sep 2026.
- The CVE record carries a CVSS v3.1 base score of 9.8 (Critical), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 1% (percentile 62), as of 29 Oct 2026. EPSS is a statistical estimate, not a report of exploitation.
- CISA's SSVC assessment in the CVE record: exploitation none, automatable yes, technical impact total.
Source: CISA KEV 2026.10.29, as of ; CVE List, as of ; FIRST EPSS, as of . About the data.
Description
Skype for Business Remote Code Execution Vulnerability
External control of file name or path in Skype for Business allows an unauthorized attacker to execute code over a network.
Source: CVE List, as of . About the data.
Weakness
CWE-73
- CWE-73: External Control of File Name or Path
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| CVE record last updated |
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- CVE-2019-1068: Microsoft SQL Server Remote Code Execution Vulnerability