CVE-2026-55145: Outlook Copilot Tampering Vulnerability

mediumCVSS 6.3CVE-2026-55145

Improper neutralization of special elements used in a command ('command injection') in Outlook Copilot allows an authorized attacker to perform tampering over a network.

CSIRTS triage

vendor: Microsoft product: Outlook CopilotOther

What: Improper neutralization of special elements used in a command ('command injection') in Outlook Copilot allows an authorized attacker to perform tampering over a network.
Who is affected: Authorized users of Outlook Copilot are affected.
Urgency: Remediation is medium urgency due to the potential for tampering.
Action: Update Outlook Copilot to the latest version.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 6.3
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55145

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-551450.37% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 30% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-55145	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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