Vulnerability record · CVE-2005-0021 · published 2 May 2005
CVE-2005-0021: University of cambridge exim vulnerability
University Of Cambridge · Exim
Multiple buffer overflows in Exim before 4.43 may allow attackers to execute arbitrary code via (1) an IPv6 address with more than 8 components, as demonstrated using the -be command line option, which triggers an overflow in the host_aton function, or (2) the -bh command line option or dnsdb PTR lookup, which triggers an overflow in the dns_build_reverse function.
Description
Multiple buffer overflows in Exim before 4.43 may allow attackers to execute arbitrary code via (1) an IPv6 address with more than 8 components, as demonstrated using the -be command line option, which triggers an overflow in the host_aton function, or (2) the -bh command line option or dnsdb PTR lookup, which triggers an overflow in the dns_build_reverse function.
AV:L/AC:L/Au:N/C:C/I:C/A:C
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2005-0021), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.