Bug 2464245 (CVE-2026-40686) - CVE-2026-40686 Exim: Exim: Information disclosure via malformed UTF-8 header data
Summary: CVE-2026-40686 Exim: Exim: Information disclosure via malformed UTF-8 header ...
Keywords:
Status: NEW
Alias: CVE-2026-40686
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
low
low
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On: 2464918 2464919 2464920
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-04-30 22:01 UTC by OSIDB Bzimport
Modified: 2026-05-04 10:18 UTC (History)
0 users

Fixed In Version:
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Description OSIDB Bzimport 2026-04-30 22:01:17 UTC 
In Exim before 4.99.2, when utf8 operators are enabled, there is an out-of-bounds read if large UTF-8 trailing characters are present (malformed UTF-8 header data). Information might be divulged within an error message produced during handling of an unrelated e-mail message.
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