CVE-2020-16969
mediumpriority · track · 18EPSS 0.027 · 86 %ileEURUUSEPSS · scored 2026-10-27
<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>
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 3.7–7.1
weaknesses
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affected products (13)
Products and version ranges known to be affected.
also known as (5)
Other names and identifiers for this entity.
sources
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references (8)
External citations — patches, advisories, analysis.
- http://www.nsfocus.net/vulndb/50101cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-16969cnnvd
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16969cnnvd
- https://portal.msrc.microsoft.com/en-us/security-guidance/releasenotedetail/2020-octPatchcnnvd
- https://portal.msrc.microsoft.com/zh-CN/security-guidance/advisory/CVE-2020-16969cnnvd
- https://vigilance.fr/vulnerability/Microsoft-Exchange-information-disclosure-33561cnnvd
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16969enisa_euvd
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16969PatchVendor Advisorynvd
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