CVE-2021-33913

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 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:*:*:*:*:*:*:*:*

Information

Published : 2022-01-19 10:15

Updated : 2022-01-26 09:40

NVD link : CVE-2021-33913

Mitre link : CVE-2021-33913

JSON object : View

CWE

CWE-787

Out-of-bounds Write

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Products Affected

libspf2_project

libspf2

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