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.

CVSS v3.0 9.8 CRITICAL
CVSS v2.0 9.3 HIGH

9.8^/10

CVSS v3.0 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

9.3^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:M/Au:N/C:C/I:C/A:C

Exploitability : 8.6 / Impact : 10.0

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://github.com/shevek/libspf2/tree/8131fe140704eaae695e76b5cd09e39bd1dd220b	Third Party Advisory
https://nathanielbennett.com/blog/libspf2-cve-jan-2022-disclosure	Exploit Third Party Advisory
https://lists.debian.org/debian-lts-announce/2022/01/msg00015.html	Mailing List Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:libspf2_project:libspf2:*:*:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

Information

Published : 2022-01-19 10:15

Updated : 2022-01-26 09:36

NVD link : CVE-2021-33912

Mitre link : CVE-2021-33912

JSON object : View

CWE

CWE-787

Out-of-bounds Write

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Products Affected

debian

debian_linux

libspf2_project

libspf2

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