CVE-2026-40684 (GCVE-0-2026-40684)
Vulnerability from cvelistv5
Published
2026-04-30 00:00
Modified
2026-05-01 17:22
Severity ?
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-684 - Incorrect Provision of Specified Functionality
Summary
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.
References
Impacted products
Vendor Product Version
Exim Exim Version: 0   ≤
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