- 7.8HighCVSS base score
- 0.47%Exploitation in 30 daysEPSS · top 59% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Use of uninitialized resource in Microsoft Office Excel allows an unauthorized attacker to execute code locally.
Timeline
ID reserved
By microsoft
- 27 days later
· 27 days later
Published
- 4 months later
· 4 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| microsoftCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C |
| NVDNVD · Analyzed | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.47% · top 59% of all CVEs (11 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
Microsoft · Microsoft 365 Apps for Enterprise
- affected 16.0.1 – < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Excel 2016
- affected 16.0.0.0 – < 16.0.5561.1001
Microsoft · Microsoft Office 2019
- affected 19.0.0 – < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office 365 for Mac
- affected 1.0.0 – < 16.111.26071215
Microsoft · Microsoft Office LTSC 2021
- affected 16.0.1 – < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office LTSC 2024
- affected 16.0.0 – < https://aka.ms/OfficeSecurityReleases
Microsoft · Microsoft Office LTSC for Mac 2021
- affected 16.0.1 – < 16.111.26071215
Microsoft · Microsoft Office LTSC for Mac 2024
- affected 16.0.0 – < 16.111.26071215
Microsoft · Office Online Server
- affected 16.0.0.0 – < 16.0.10417.20175
References
References1
- Microsoft Excel Remote Code Execution Vulnerability (opens in a new tab)vendor-advisorypatch
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-44231 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-55949)Record last updated .