Improper Access Control Affecting thunderbird package, versions [,153.6)[154,159)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published27 Oct 2026
- disclosed27 Oct 2026
- creditUnknown
Introduced: 27 Oct 2026
NewCVE-2026-118176 (opens in a new tab)How to fix?
Upgrade thunderbird to version 153.6, 159 or higher.
Overview
Affected versions of this package are vulnerable to Improper Access Control via the handling of mailbox: URLs with extended-length UNC paths. An attacker can cause the application to connect to an attacker-controlled SMB server, resulting in disclosure of the user's Windows account name and NTLM authentication data, which may be leveraged for offline password cracking or relay attacks, by enticing a user to view a specially crafted email. This is only exploitable if the application is running on Windows.