CVE-2020-16949
Microsoft Outlook Denial of Service Vulnerability
No known exploitation. EPSS puts it in the 87th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
<p>A denial of service vulnerability exists in Microsoft Outlook software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could cause a remote denial of service against a system.</p> <p>Exploitation of the vulnerability requires that a specially crafted email be sent to a vulnerable Outlook server.</p> <p>The security update addresses the vulnerability by correcting how Microsoft Outlook handles objects in memory.</p>
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
3.0% chance of exploitation activity in the next 30 days, which ranks it in the 87th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 2078 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified
Affected products
- windows 10Operating Systems / windows
- windows 7Operating Systems / windows
- windows 8.1Operating Systems / windows
- windows rt 8.1Operating Systems / windows
- windows server 2008Operating Systems / windows
- windows server 2012Operating Systems / windows
- windows server 2016Operating Systems / windows
- windows server 2019Operating Systems / windows
And 13 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Scored 4.7 by NVD.
How it is reached
- Attack Vector LocalRequires local access to the vulnerable system (e.g. local login, malicious file)
- Attack Complexity HighRequires specific conditions like a race condition or non-default configuration
- Privileges Required LowRequires basic user-level privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity NoneNo integrity impact
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
Sources
References in the record
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