CVE-2021-33912

Name	CVE-2021-33912
Description	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.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-2890-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libspf2 (PTS)	buster, buster (security)	1.2.10-7.1~deb10u1	fixed
	bullseye (security), bullseye	1.2.10-7.1~deb11u1	fixed
	bookworm	1.2.10-7.2	fixed
	trixie	1.2.10-8	fixed
	sid	1.2.10-8.2	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Origin
libspf2	source	stretch	1.2.10-7+deb9u2	DLA-2890-1
libspf2	source	buster	1.2.10-7.1~deb10u1
libspf2	source	bullseye	1.2.10-7.1~deb11u1
libspf2	source	(unstable)	1.2.10-7.1

Notes

https://nathanielbennett.com/blog/libspf2-cve-jan-2022-disclosure
https://github.com/shevek/libspf2/pull/35
https://github.com/shevek/libspf2/commit/28faf4624a6a371b11afdb9820078d3b0ee3803d