CVE detail
CVE-2026-40684
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.
Buzz score
Why this CVE is surfacing
This all-time snapshot uses the same composite formula as Trending across a 30-year evidence window, rather than a current rolling window.
Buzz score components · mention 17.9 · diversity 11.5 · KEV 0.0 · OTX 0.0 · PoC 0.0
Why it matters now
Mention timeline
- Total mentions
- 0
- within the 30d window
- Peak daily
- 0
- highest bucket
Evidence
Source links by recency
5 source links · newest first
- http://www.openwall.com/lists/oss-security/2026/05/01/11www.openwall.com
No excerpt available.
Exploitwww.openwall.comApr 30, 2026, 10:16 PM - https://www.openwall.com/lists/oss-security/2026/04/30/21www.openwall.com
No excerpt available.
Exploitwww.openwall.comApr 30, 2026, 10:16 PM No excerpt available.
Vendor Advisoryexim.orgApr 30, 2026, 10:16 PMNo excerpt available.
Vendor Advisoryexim.orgApr 30, 2026, 10:16 PMNo excerpt available.
Vendor Advisorycode.exim.orgApr 30, 2026, 10:16 PM
Exploit code
Public exploit repository references
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0 repository references · best confidence N/A · max 0 stars
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