CVE-2021-33912

libspf2 before 1.2.11 has a four-byte heap-based buffer overflow that might allow remote attackers to execute arbitrary code (via an unauthenticated e-mail message from anywhere on the Internet) with a crafted SPF DNS record, because of incorrect sprintf usage in SPF_record_expand_data in spf_expand.c. The vulnerable code may be part of the supply chain of a site's e-mail infrastructure (e.g., with additional configuration, Exim can use libspf2; the Postfix web site links to unofficial patches for use of libspf2 with Postfix; older versions of spfquery relied on libspf2) but most often is not.

Affected products

Alt Linux, Exim, Linuxmint, Postfix, Ubuntu, Libspf2

libspf2 Project libspf2

< 1.2.11

Fix

Available

CVSS 3.1

9.8 CRITICAL

EPSS

9.6% (95th percentile)

Weakness

CWE-787

NVD status

Modified

Published

2022-01-19

No exploit for CVE-2021-33912 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.