CVE-1999-1164
MediumExploitation Probability (EPSS)
Very high risk96th percentile - higher than 96% of all known CVEs
Summary
The Microsoft Outlook client allows remote attackers to cause a denial of service by sending multiple email messages with the same X-UIDL headers, which causes Outlook to hang.
Risk Assessment
Attackers can exploit this vulnerability to disrupt user operations, potentially leading to a loss of productivity within the organization.
Recommendation
It is recommended to monitor and filter email messages to prevent the sending of messages with duplicate X-UIDL headers.
Other vulnerabilities in Microsoft Outlook
See all- CVE-2025-21361High
A vulnerability in Microsoft Outlook allows for remote code execution, potentially enabling an attacker to take control of the user's system. This flaw can be exploited by sending a specially crafted email.
- CVE-2017-11776High
Microsoft Outlook 2016 allows an attacker to obtain the email content of a user due to how it discloses this information.
- CVE-2017-8663High
Microsoft Outlook versions 2007 SP3, 2010 SP2, 2013 SP1, 2013 RT SP1, and 2016 contain a remote code execution vulnerability due to improper parsing of specially crafted email messages.
- CVE-2017-8571High
Microsoft Outlook versions 2007 SP3, 2010 SP2, 2013 SP1, 2013 RT SP1, and 2016 contain a vulnerability that allows a security feature bypass due to the way it handles input.
- CVE-2016-3278High
Microsoft Outlook 2010 SP2, 2013 SP1, 2013 RT SP1, and 2016 contains a vulnerability that allows remote attackers to execute arbitrary code via a crafted Office document.
- CVE-2024-21413CriticalActively exploited
Remote code execution vulnerability in Microsoft Outlook. Allows an attacker to execute code remotely on the victim's machine.
- CVE-2024-21378High
Remote code execution vulnerability in Microsoft Outlook. Allows an attacker to execute code remotely in the context of the user.
- CVE-2023-35311HighActively exploited
A vulnerability in Microsoft Outlook allows for a security feature bypass, potentially leading to unauthorized access to user data.
- CVE-2023-33131High
A vulnerability in Microsoft Outlook allows for remote code execution, potentially leading to full control over the user's system. An attacker can exploit this flaw through specially crafted email messages.
- CVE-2024-43482Medium
Information disclosure vulnerability in Microsoft Outlook for iOS. Could allow unauthorized access to data.
Original NVD description (English source)
Microsoft Outlook client allows remote attackers to cause a denial of service by sending multiple email messages with the same X-UIDL headers, which causes Outlook to hang.