Vulnerability Details : 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.
Vulnerability category: OverflowMemory CorruptionExecute code
Products affected by CVE-2021-33913
- cpe:2.3:a:libspf2_project:libspf2:*:*:*:*:*:*:*:*
Exploit prediction scoring system (EPSS) score for CVE-2021-33913
2.46%
Probability of exploitation activity in the next 30 days
EPSS Score History
~ 90 %
Percentile, the proportion of vulnerabilities that are scored at or less
CVSS scores for CVE-2021-33913
Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Score Source | First Seen |
---|---|---|---|---|---|---|
9.3
|
HIGH | AV:N/AC:M/Au:N/C:C/I:C/A:C |
8.6
|
10.0
|
NIST | |
9.8
|
CRITICAL | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
3.9
|
5.9
|
NIST |
CWE ids for CVE-2021-33913
-
The product writes data past the end, or before the beginning, of the intended buffer.Assigned by: nvd@nist.gov (Primary)
References for CVE-2021-33913
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https://github.com/shevek/libspf2/tree/8131fe140704eaae695e76b5cd09e39bd1dd220b
GitHub - shevek/libspf2 at 8131fe140704eaae695e76b5cd09e39bd1dd220bThird Party Advisory
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https://nathanielbennett.com/blog/libspf2-cve-jan-2022-disclosure
CVE-2021-33912 and CVE-2021-33913: Heap overflows in email validation library LibSPF2 | Nathaniel BennettExploit;Third Party Advisory
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https://security.gentoo.org/glsa/202401-22
libspf2: Multiple vulnerabilities (GLSA 202401-22) — Gentoo security
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https://lists.debian.org/debian-lts-announce/2022/01/msg00015.html
[SECURITY] [DLA 2890-1] libspf2 security updateMailing List;Third Party Advisory
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