Description
Exim 4.88 before 4.99.4, in some proxy configurations, mishandles certain short payloads, leading to disclosure of uninitialized stack memory values to a client.
Affected products
exim: exim
References4
- exim.org/static/doc/security/EXIM-Security-2026-05-19.1 Vendor Advisory
- www.openwall.com/lists/oss-security/2026/05/29/3 Mailing ListMitigationThird Party Advisory
- www.openwall.com/lists/oss-security/2026/05/29/3 Mailing ListMitigationThird Party Advisory
- lists.debian.org/debian-lts-announce/2026/06/msg00004.html
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 18 · as of 15 November 2026
- CWE
- CWE-839
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