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CVE-2026-40684
Published: Apr 30, 2026
Modified: May 1, 2026
PUBLISHED
CVSS v3.1
5.9
MEDIUM
Description
In Exim before 4.99.2, on systems using musl libc (not glibc), an attacker can crash the connection instance when malformed DNS data is present in PTR records. This is caused by a dn_expand oddity in octal printing.
| Vendor | Product | Versions |
|---|---|---|
Exim | Exim | affected 0 - < 4.99.2 |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
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