Out-of-bounds Write Affecting libspf2 package, versions <1.2.10-7ubuntu0.18.04.1~esm1


Severity

Recommended
medium

Based on Ubuntu security rating.

Threat Intelligence

EPSS
1.35% (81st percentile)

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  • Snyk IDSNYK-UBUNTU1804-LIBSPF2-2355067
  • published21 Jan 2022
  • disclosed19 Jan 2022

Introduced: 19 Jan 2022

CVE-2021-33913  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade Ubuntu:18.04 libspf2 to version 1.2.10-7ubuntu0.18.04.1~esm1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream libspf2 package and not the libspf2 package as distributed by Ubuntu. See How to fix? for Ubuntu:18.04 relevant fixed versions and status.

libspf2 before 1.2.11 has a 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 SPF_record_expand_data in spf_expand.c. The amount of overflowed data depends on the relationship between the length of an entire domain name and the length of its leftmost label. 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.

CVSS Base Scores

version 3.1