Description
Exim before 4.100.1 allows SMTP smuggling in which the received message does not match any sent message, and instead depends on crafted data sent after a rejection during DATA processing.
Affected products
exim: exim
References1
- lists.exim.org/lurker/message/20260918.121220.0f87338e.en.html Vendor Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 9 · as of 8 November 2026
- CWE
- CWE-93
Could this be exploited in your environment?
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