onyx --cves cve-2026-40684
CVE-2026-40684
- score
- <0.1
- cvss
- 5.9
- epss
- 0.6%
- published
- 2026-04-30
- kev added
- —
- first seen
Exim < 4.99.2 on systems using musl libc contains a denial of service caused by dn_expand octal printing oddity in PTR record processing, letting attackers crash connection instances remotely, exploit requires malformed DNS PTR records.
Timeline
How this CVE moved toward exploitation. Chart: last 30 days — trend score, EPSS, community mentions per day; hover the event lane.
- Published
- Tracked by Onyx
Weaknesses
References 6
- https://exim.org/static/doc/security/cve-2026-04.1/CVE2026-40684.assessment
- https://www.openwall.com/lists/oss-security/2026/04/30/21
- https://exim.org/static/doc/security/CVE-2026-40684.txt
- http://www.openwall.com/lists/oss-security/2026/05/01/11
- https://code.exim.org/exim/exim/commit/628bbaca7672748d941a12e7cd5f0122a4e18c81
- https://exim.org/static/doc/security/CVE-2025-40684.txt