Security September 2026 CVE-2026-100208
Integer overflow or wraparound in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
Severity Important
CVSS base score 7.5
Impact Remote Code Execution
Exploitation detected No known exploitation (MSRC assessment)
Exploitability Exploitation Less Likely
Publicly disclosed No (MSRC assessment)
EPSS · 30-day forecast 0.5% FIRST forecast dated 10 Nov 2026, for the following 30 days · FIRST percentile 39.5% · about EPSS
Customer action Required: follow the MSRC remediation guidance More details
CVSS vector CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Public detection template No Nuclei template is listed in the current collected catalog
Component Microsoft Office Outlook
Weakness CWE-190: Integer Overflow or Wraparound
Issued by Microsoft
Last revised 25 Sep 2026 CVSS 3.1 base metrics Red raises the risk · green lowers it
Attack vector NetworkAV:N
Attack complexity HighAC:H
Privileges required NonePR:N
User interaction RequiredUI:R
Scope UnchangedS:U
Confidentiality HighC:H
Integrity HighI:H
Availability HighA:H
0 KBs No KB listed No KB update is listed in the collected MSRC record. Check the MSRC advisory for product releases and other remedies.
Source. This summary comes from MSRC's public CVRF document for September 2026. If the MSRC page is blocked in your browser, the NVD and CVE.org records carry the same identifier. None of this says whether your devices are affected.
Detection template: Unknown: detection-template evidence is incomplete or retained → No Nuclei template listed
6 Nov 2026 · 17:32:22 UTC Detection template: No Nuclei template listed → Unknown: detection-template evidence is incomplete or retained
6 Nov 2026 · 16:31:02 UTC
Changes are dated when recorded; day views use the last saved version from that UTC day, and citations stay fixed.
Cite this version Field-level log (16)
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10 Nov 2026 · 18:32:11 UTC
EPSS 0.5%; scored 9 Nov 2026 → 0.5%; scored 10 Nov 2026 9 Nov 2026 · 22:24:37 UTC
EPSS 0.5%; scored 8 Nov 2026 → 0.5%; scored 9 Nov 2026 8 Nov 2026 · 15:16:05 UTC
EPSS 0.5%; scored 7 Nov 2026 → 0.5%; scored 8 Nov 2026 7 Nov 2026 · 16:12:44 UTC
EPSS 0.5%; scored 6 Nov 2026 → 0.5%; scored 7 Nov 2026 6 Nov 2026 · 19:15:37 UTC
EPSS 0.5%; scored 5 Nov 2026 → 0.5%; scored 6 Nov 2026 6 Nov 2026 · 17:32:22 UTC
Public detection template Unknown: detection-template evidence is incomplete or retained → No Nuclei template listed 6 Nov 2026 · 17:32:22 UTC
Source coverage: public-exploit-code Incomplete → Current 6 Nov 2026 · 17:32:22 UTC
Source coverage: first-epss Incomplete → Current 6 Nov 2026 · 17:32:22 UTC
Source coverage: msrc-cvrf Incomplete → Current 6 Nov 2026 · 16:31:02 UTC
Public detection template No Nuclei template listed → Unknown: detection-template evidence is incomplete or retained 6 Nov 2026 · 16:31:02 UTC
Source coverage: public-exploit-code Current → Incomplete 6 Nov 2026 · 16:31:02 UTC
Source coverage: first-epss Current → Incomplete 6 Nov 2026 · 16:31:02 UTC
Source coverage: msrc-cvrf Current → Incomplete 5 Nov 2026 · 23:42:03 UTC
EPSS 0.5%; scored 4 Nov 2026 → 0.5%; scored 5 Nov 2026 5 Nov 2026 · 02:36:20 UTC
EPSS 0.5%; scored 3 Nov 2026 → 0.5%; scored 4 Nov 2026 4 Nov 2026 · 03:04:37 UTC
EPSS 0.5%; scored 2 Nov 2026 → 0.5%; scored 3 Nov 2026 Explore global source statements, affected packages and advisory history for CVE-2026-100208 . The catalog has a separate collection scope from Microsoft release records.