CVE-2023-35636
Published: 12 December 2023
Summary
CVE-2023-35636 is a medium-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Microsoft Office. Its CVSS base score is 6.5 (Medium).
Operationally, ranked in the top 6.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis
Microsoft Outlook contains an information disclosure vulnerability tracked as CVE-2023-35636. The flaw is rated 6.5 under CVSS 3.1 with the vector AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N and is associated with CWE-200. It affects the Microsoft Outlook client and permits exposure of sensitive information without requiring authentication.
An unauthenticated remote attacker can exploit the issue by sending a specially crafted message or link that a user must interact with, resulting in disclosure of confidential data from the victim's Outlook instance while leaving integrity and availability unaffected.
Microsoft has published remediation guidance in its Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-35636, which includes available updates and configuration recommendations for affected Outlook versions. The associated EPSS score has remained near 0.11 with only minor fluctuation between its recorded peak and current value.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-39636
Vulnerability details
Microsoft Outlook Information Disclosure Vulnerability
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Automated marking applies security attributes to system outputs, making it harder for attackers to exploit unmarked sensitive information leading to unauthorized exposure.
Proper attribute retention and permitted-value enforcement limits unauthorized actors from accessing sensitive information lacking correct labels.
Prevents unauthorized exposure of sensitive information by prohibiting untrusted external systems from processing or storing it.
By enforcing authorization matching prior to sharing, the control reduces the risk of exposing sensitive information to unauthorized actors.
Review and removal of nonpublic information from publicly accessible systems directly prevents exposure of sensitive data to unauthorized actors.
Data mining protection mechanisms detect and block unauthorized bulk extraction of sensitive data, directly mitigating exposure to unauthorized actors.
Literacy training teaches users to recognize and avoid actions that result in unauthorized exposure of sensitive information.
Retaining and monitoring training records confirms personnel have completed privacy and security awareness training on handling sensitive data, reducing the chance of unauthorized exposure due to lack of knowledge.