Out-of-bounds Read Affecting thunderbird package, versions [,140.9.0)[141.0.0,149.0.0)
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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Test your applications- Snyk IDSNYK-UNMANAGED-THUNDERBIRD-15763369
- published25 Mar 2026
- disclosed24 Mar 2026
- creditRintaro Kobayashi
Introduced: 24 Mar 2026
CVE-2026-4371 (opens in a new tab)How to fix?
Upgrade thunderbird to version 140.9.0, 149.0.0 or higher.
Overview
Affected versions of this package are vulnerable to Out-of-bounds Read via the IMAP parsing process. An attacker can cause the application to crash or access sensitive memory contents by sending specially crafted IMAP responses containing malformed strings with negative lengths from a malicious or compromised mail server.