Vulnerability in Microsoft Exchange Server
CVE-2020-16969
<p>An information disclosure vulnerability exists in how Microsoft Exchange validates tokens when handling certain messages. An attacker who successfully exploited the vulnerability could use this to gain further information from a user.</p> <p>To exploit the vulnerability, an attacker could include specially crafted OWA messages that could be loaded, without warning or filtering, from the attacker-controlled URL. This callback vector provides an information disclosure tactic used in web beacons and other types of tracking systems.</p> <p>The security update corrects the way that Exchange handles these token validations.</p>
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.027 (85.6th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 86th percentile — 85.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.027 · newest: 0.027 · change: 0.000
Affected products
- Microsoft Exchange Server — versions 2013, 2016, 2019
- Microsoft Exchange Server 2013 Cumulative Update 23 — versions 15.00.0
- Microsoft Exchange Server 2016 Cumulative Update 17 — versions 15.01.0
- Microsoft Exchange Server 2016 Cumulative Update 18 — versions 15.01.0
- Microsoft Exchange Server 2019 Cumulative Update 6 — versions 15.02.0
- Microsoft Exchange Server 2019 Cumulative Update 7 — versions 15.02.0
References
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16969 (Patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2020-16969?
- CVE-2020-16969 is a high-severity vulnerability in Microsoft Exchange Server. CVSS score: 7.1/10. Published 2020-10-16.
- How severe is CVE-2020-16969?
- High severity. CVSS v3 base score is 7.1 out of 10.