Microsoft Exchange Server up to 2010 SP3 Outlook Web Access /owa/auth/logon.aspx username server-side request forgery

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability classified as critical has been found in Microsoft Exchange Server up to 2010 SP3 (Groupware Software). This affects some unknown functionality of the file /owa/auth/logon.aspx of the component Outlook Web Access. The manipulation of the argument username as part of a Parameter leads to a server-side request forgery vulnerability. CWE is classifying the issue as CWE-918. 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. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Rollup 18 for Microsoft Exchange Server 2010 SP3 and previous versions has an SSRF vulnerability via the username parameter in /owa/auth/logon.aspx in the OWA (Outlook Web Access) login page.

The bug was discovered 12/13/2018. The weakness was released 09/21/2018 as not defined mailinglist post (Bugtraq). It is possible to read the advisory at This vulnerability is uniquely identified as CVE-2018-16793 since 09/10/2018. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 05/17/2023).

By approaching the search of inurl:owa/auth/logon.aspx it is possible to find vulnerable targets with Google Hacking.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.







CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.9

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.6
NVD Vector: 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Server-side request forgery
CWE: CWE-918
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined
Google Hack: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍


09/10/2018 🔍
09/17/2018 +7 days 🔍
09/21/2018 +3 days 🔍
09/21/2018 +0 days 🔍
09/22/2018 +1 days 🔍
12/13/2018 +82 days 🔍
05/17/2023 +1616 days 🔍



Advisory: 149411
Status: Not defined

CVE: CVE-2018-16793 (🔍)
SecurityFocus: 105386 - Rollup 18 for Microsoft Exchange Server Server Side Request Forgery Security Bypass Vulnerability


Created: 09/22/2018 07:48 AM
Updated: 05/17/2023 02:48 PM
Changes: 09/22/2018 07:48 AM (62), 03/26/2020 02:51 PM (3), 05/17/2023 02:48 PM (3)
Complete: 🔍


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