CVE-2026-40686
Low
Description
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.
SeverityLow
CVSS3.7
Exploit probability—
Product
Exim
PublishedApr 30, 2026
First seenApr 30, 2026
Weakness typeCWE-125Out-of-bounds read
How to fix
Update
- exim exim4.99.2 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| exim exim | v < 4.99.2 | 4.99.2 |
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