CVE-2021-33912: Buffer Overflow

Published Jan 19, 2022
·
Updated

Last updated 24 July 2024

Other sources

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 SPFrecordexpanddata in spfexpand.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 Software

3 affected componentsFixes available
debian/libspf2
1.2.10-7.1~deb11u11.2.10-7.21.2.10-8.2
Libspf2 Project Libspf2<1.2.11
Debian Debian Linux=9.0

Event History

Jan 19, 2022
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
Description
Jan 19, 2024
Data Sourced
via Launchpad·09:07 PM
Description
Sep 15, 2024
Data Sourced
via Ubuntu·09:48 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is CVE-2021-33912?

CVE-2021-33912 is a vulnerability in libspf2 before 1.2.11 that allows remote attackers to execute arbitrary code with a crafted SPF DNS record.

2

How severe is CVE-2021-33912?

CVE-2021-33912 has a severity rating of 9.8 (critical).

3

Which software versions are affected by CVE-2021-33912?

Versions of libspf2 before 1.2.11 and Debian Linux 9.0 are affected by CVE-2021-33912.

4

How can the vulnerability be fixed?

To fix CVE-2021-33912, upgrade to libspf2 version 1.2.11 or apply the necessary security patches.

5

Is there any additional information about CVE-2021-33912?

Yes, you can find more information about CVE-2021-33912 in the provided references.

Contact

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