CVE-2023-23397: Microsoft Office Outlook Privilege Escalation Vulnerability
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
Microsoft Office Outlook contains a privilege escalation vulnerability that allows for a NTLM Relay attack against another service to authenticate as the user.
CSIRTS triage
- What
- Microsoft Office Outlook contains a privilege escalation vulnerability that allows for a NTLM Relay attack against another service.
- Who is affected
- Users of Microsoft Office Outlook.
- Urgency
- Remediation is urgent due to active exploitation and critical severity.
- Action
- Apply the latest updates for Microsoft Office Outlook.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2023-23397
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.
- Exploitation confirmedCVE-2023-23397Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 100% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2023-23397 | coverage & exploitation status | NVD · CVE.org |
Recent advisories for Microsoft Office Outlook
A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.
- criticalexploitedCVE-2017-11774: Microsoft Office Outlook Security Feature Bypass Vulnerabilitycisa-kev · 2021-11-03
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