CVE-2021-33913 describes a critical heap-based buffer overflow in libspf2 versions prior to 1.2.11, specifically within the SPF_record_expand_data function. This vulnerability could allow remote attackers to execute arbitrary code by sending an unauthenticated email with a crafted SPF DNS record, potentially impacting email infrastructure that utilizes libspf2. Rated with a CVSS score of 9.8 (Critical), this vulnerability is easily exploitable over the network with low attack complexity and no user interaction required, leading to potential complete compromise of confidentiality, integrity, and availability. The overflow amount depends on the domain name and label lengths. Currently, there is no evidence of active exploitation, and no public exploit code is available in Metasploit, Nuclei, or ExploitDB. Community discussion and media coverage for this CVE are minimal, which is typical for a large percentage of reported vulnerabilities.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
< 1.2.11CPE matchmatch criteria | cpe:2.3:a:libspf2_project:libspf2:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.
Remediation records are not available for this CVE.