Vulnerabilities
Misconfiguration
Compliance
CVE Vulnerabilities

CVE-2021-26855

Server-Side Request Forgery (SSRF)

Published: Mar 03, 2021 | Modified: Oct 30, 2025
CVSS 3.x
9.8
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
7.5 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P
RedHat/V2
RedHat/V3
Ubuntu
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-26855
CWEhttps://cwe.mitre.org/data/definitions/918.html

Microsoft Exchange Server Remote Code Execution Vulnerability

Weakness

The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Affected Software

NameVendorStart VersionEnd Version
Exchange_serverMicrosoft2013-cumulative_update_21 (including)2013-cumulative_update_21 (including)
Exchange_serverMicrosoft2013-cumulative_update_22 (including)2013-cumulative_update_22 (including)
Exchange_serverMicrosoft2013-cumulative_update_23 (including)2013-cumulative_update_23 (including)
Exchange_serverMicrosoft2016-cumulative_update_10 (including)2016-cumulative_update_10 (including)
Exchange_serverMicrosoft2016-cumulative_update_11 (including)2016-cumulative_update_11 (including)
Exchange_serverMicrosoft2016-cumulative_update_12 (including)2016-cumulative_update_12 (including)
Exchange_serverMicrosoft2016-cumulative_update_13 (including)2016-cumulative_update_13 (including)
Exchange_serverMicrosoft2016-cumulative_update_14 (including)2016-cumulative_update_14 (including)
Exchange_serverMicrosoft2016-cumulative_update_15 (including)2016-cumulative_update_15 (including)
Exchange_serverMicrosoft2016-cumulative_update_16 (including)2016-cumulative_update_16 (including)
Exchange_serverMicrosoft2016-cumulative_update_17 (including)2016-cumulative_update_17 (including)
Exchange_serverMicrosoft2016-cumulative_update_18 (including)2016-cumulative_update_18 (including)
Exchange_serverMicrosoft2016-cumulative_update_19 (including)2016-cumulative_update_19 (including)
Exchange_serverMicrosoft2016-cumulative_update_8 (including)2016-cumulative_update_8 (including)
Exchange_serverMicrosoft2016-cumulative_update_9 (including)2016-cumulative_update_9 (including)
Exchange_serverMicrosoft2019 (including)2019 (including)
Exchange_serverMicrosoft2019-cumulative_update_1 (including)2019-cumulative_update_1 (including)
Exchange_serverMicrosoft2019-cumulative_update_2 (including)2019-cumulative_update_2 (including)
Exchange_serverMicrosoft2019-cumulative_update_3 (including)2019-cumulative_update_3 (including)
Exchange_serverMicrosoft2019-cumulative_update_4 (including)2019-cumulative_update_4 (including)
Exchange_serverMicrosoft2019-cumulative_update_5 (including)2019-cumulative_update_5 (including)
Exchange_serverMicrosoft2019-cumulative_update_6 (including)2019-cumulative_update_6 (including)
Exchange_serverMicrosoft2019-cumulative_update_7 (including)2019-cumulative_update_7 (including)
Exchange_serverMicrosoft2019-cumulative_update_8 (including)2019-cumulative_update_8 (including)

References

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