CVE catalog

CVE-2021-33912

libspf2: CVE-2021-33912

Severity: Medium
Published: Jan 19, 2022, 6:15:00 PM UTC
Source: [NVD] · [CVE record]
EPSS: 9.64% · Oct 25, 2026

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.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	libspf2	sid	`1.2.10-11`	fixed
Debian	libspf2	forky	`1.2.10-11`	fixed
Debian	libspf2	trixie	`1.2.10-8.3`	fixed
Debian	libspf2	bookworm	`1.2.10-7.2`	fixed
Alpine	libspf2	3.14	`1.2.11-r0`	fixed
Alpine	libspf2	3.15	`1.2.11-r0`	fixed
Alpine	libspf2	3.16	`1.2.11-r0`	fixed
Alpine	libspf2	3.17	`1.2.11-r0`	fixed
Alpine	libspf2	3.18	`1.2.11-r0`	fixed
Alpine	libspf2	3.19	`1.2.11-r0`	fixed
Alpine	libspf2	3.20	`1.2.11-r0`	fixed
Alpine	libspf2	3.21	`1.2.11-r0`	fixed
Alpine	libspf2	3.22	`1.2.11-r0`	fixed
Alpine	libspf2	3.23	`1.2.11-r0`	fixed
Alpine	libspf2	3.24	`1.2.11-r0`	fixed
Ubuntu	libspf2	pro	`1.2.10-6`	vulnerable
Ubuntu	libspf2	pro	`1.2.10-6build1`	vulnerable
Ubuntu	libspf2	pro	`1.2.10-6ubuntu0.1~esm1`	vulnerable
Ubuntu	libspf2	pro	`1.2.10-6ubuntu0.1~esm2`	fixed
Ubuntu	libspf2	pro	`1.2.10-7build2`	vulnerable
Ubuntu	libspf2	pro	`1.2.10-7ubuntu0.18.04.1~esm1`	fixed
Ubuntu	libspf2	20.04	`1.2.10-7build3`	vulnerable
Ubuntu	libspf2	20.04	`1.2.10-7build4`	vulnerable
Ubuntu	libspf2	20.04	`1.2.10-7+deb9u2build0.20.04.1`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	libspf2	source	sid	`1.2.10-7.1`	not yet assigned	Not reported	Not reported
Debian	libspf2	source	forky	`1.2.10-7.1`	not yet assigned	Not reported	Not reported
Debian	libspf2	source	trixie	`1.2.10-7.1`	not yet assigned	Not reported	Not reported
Debian	libspf2	source	bookworm	`1.2.10-7.1`	not yet assigned	Not reported	Not reported
Alpine	libspf2	apk	3.14	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.15	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.16	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.17	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.18	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.19	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.20	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.21	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.22	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.23	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Alpine	libspf2	apk	3.24	`1.2.11-r0`	Not reported	ALPINE-CVE-2021-33912	Not reported
Ubuntu	libspf2	deb	pro	`1.2.10-6ubuntu0.1~esm2`	Not reported	USN-6584-2	Not reported
Ubuntu	libspf2	deb	pro	`1.2.10-7ubuntu0.18.04.1~esm1`	Not reported	UBUNTU-CVE-2021-33912	Not reported
Ubuntu	libspf2	deb	20.04	`1.2.10-7+deb9u2build0.20.04.1`	Not reported	UBUNTU-CVE-2021-33912	Not reported

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[libmail-spf-xs-perl]Fixed
Source package: [libspf2]
Details (2)
- 1.2.10-7.2+b1 · amd64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12
- 1.2.10-7.2+b1 · arm64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12
[libspf2-2]Fixed
Source package: [libspf2]
Details (2)
- 1.2.10-7.2+b1 · amd64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12
- 1.2.10-7.2+b1 · arm64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12
[libspf2-2-dbg]Fixed
Source package: [libspf2]
Details (2)
- 1.2.10-7.2+b1 · amd64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12
- 1.2.10-7.2+b1 · arm64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12
[libspf2-dev]Fixed
Source package: [libspf2]
Details (2)
- 1.2.10-7.2+b1 · amd64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12
- 1.2.10-7.2+b1 · arm64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12
[spfquery]Fixed
Source package: [libspf2]
Details (2)
- 1.2.10-7.2+b1 · amd64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12
- 1.2.10-7.2+b1 · arm64 · bookworm
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · bookworm; dsa · libspf2 · debian · 12

[Debian 13 (Trixie)]

[libmail-spf-xs-perl]Fixed
Source package: [libspf2]
Details (2)
- 1.2.10-8.3 · amd64 · trixie
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · 13
- 1.2.10-8.3 · arm64 · trixie
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · 13
[libspf2-2t64]Fixed
Source package: [libspf2]
Details (2)
- 1.2.10-8.3 · amd64 · trixie
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · 13
- 1.2.10-8.3 · arm64 · trixie
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · 13
[libspf2-dev]Fixed
Source package: [libspf2]
Details (2)
- 1.2.10-8.3 · amd64 · trixie
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · 13
- 1.2.10-8.3 · arm64 · trixie
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · 13
[spfquery]Fixed
Source package: [libspf2]
Details (2)
- 1.2.10-8.3 · amd64 · trixie
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · 13
- 1.2.10-8.3 · arm64 · trixie
  Fixed · Fixed: 1.2.10-7.1
  dsa · libspf2 · debian · 13

Observed: Oct 23, 2026, 5:58:05 PM UTC

References

[Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database]