What is CVE-2026-118711?
Stack-based buffer overflow in Microsoft Office Excel allows an unauthorized attacker to execute code over a network.
The record classifies CVE-2026-118711 under weakness class CWE-121. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs a user to take an action first, and has high impact on confidentiality, integrity, availability. 7 affected-product entries are recorded, across 1 vendor, listed below. The identifier was first published 1 day ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 8.8 — HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C - CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 4.4/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2026-11-10
Is CVE-2026-118711 being exploited?
It currently carries a trending score of 35 in the Threadlinqs vulnerability feed.
Affected products and versions
- Microsoft: 365 Apps for Enterprise, Office 365 for Mac, Office LTSC 2021, Office LTSC 2024, Office LTSC for Mac 2021, Office LTSC for Mac 2024, Office Online Server
How to fix CVE-2026-118711
Patch reference: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-118711. Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.
Threat activity tracking CVE-2026-118711
1 tracked threat in the Threadlinqs corpus references CVE-2026-118711, either in the campaign’s CVE list or as an indicator on the campaign record.
Sources
Enriched from CVE.org, NVD, GitHub Security Advisories. This product uses the NVD API but is not endorsed or certified by the NVD.