PT-2022-10299 · Exim+5 · Exim+5

Published 2021-10-15 · Updated 2024-11-26 · CVE-2021-33912

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions libspf2 versions prior to 1.2.11

Description The issue is related to 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. This is due to 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, but most often it is not.

Recommendations For versions prior to 1.2.11, update to version 1.2.11 or later to resolve the issue. As a temporary workaround, consider restricting the use of libspf2 in e-mail infrastructure configurations until a patch is applied. Avoid using libspf2 with additional configuration in Exim or with unofficial patches for Postfix until the issue is resolved.

Exploit

Fix

RCE

Memory Corruption

Weakness Enumeration

CWE-787

Related Identifiers

ALT-PU-2021-3046

ALT-PU-2022-2548

ALT-PU-2024-1215

CVE-2021-33912

DLA-2890-1

ROSA-SA-2024-2528

USN-6584-1

USN-6584-2

Affected Products

Alt Linux

Exim

Linuxmint

Postfix

Ubuntu

Libspf2

References · 23

• 🔥 https://nathanielbennett.com/blog/libspf2-cve-jan-2022-disclosure · Exploit
• https://ubuntu.com/security/notices/USN-6584-1 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2021-33912 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-33912 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-6584-2 · Vendor Advisory
• https://security.gentoo.org/glsa/202401-22 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2021-33912 · Security Note
• https://osv.dev/vulnerability/DLA-2890-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2021-33913 · Vendor Advisory
• https://osv.dev/vulnerability/USN-6584-1 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2021-33912 · Vendor Advisory
• https://osv.dev/vulnerability/ALPINE-CVE-2021-33912 · Vendor Advisory
• https://ubuntu.com/security/CVE-2021-33912 · Vendor Advisory
• https://osv.dev/vulnerability/USN-6584-2 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2021-33912 · Vendor Advisory