CVEvulnerability
CVE-2026-40684
7.5 HIGH
Official page ↗
- Status
- Modified
- Published
- 2026-04-30
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 5.9 MEDIUM — CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- CVSS 3.1 ([email protected])
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-684
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.
Affected configurations
• exim exim (< 4.99.2)
Related
Weakness · CWE (1)
- CWE-684 Incorrect Provision of Specified Functionality weakness
References
- https://code.exim.org/exim/exim/commit/628bbaca7672748d941a12e7cd5f0122a4e18c81 Patch
- https://exim.org/static/doc/security/CVE-2026-40684.txt Broken Link
- https://exim.org/static/doc/security/cve-2026-04.1/CVE2026-40684.assessment Vendor Advisory
- https://www.openwall.com/lists/oss-security/2026/04/30/21 Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2026/05/01/11 www.openwall.com