8.1

CVE-2021-32749

Exploit
fail2ban is a daemon to ban hosts that cause multiple authentication errors. In versions 0.9.7 and prior, 0.10.0 through 0.10.6, and 0.11.0 through 0.11.2, there is a vulnerability that leads to possible remote code execution in the mailing action mail-whois. Command `mail` from mailutils package used in mail actions like `mail-whois` can execute command if unescaped sequences (`\n~`) are available in "foreign" input (for instance in whois output). To exploit the vulnerability, an attacker would need to insert malicious characters into the response sent by the whois server, either via a MITM attack or by taking over a whois server. The issue is patched in versions 0.10.7 and 0.11.3. As a workaround, one may avoid the usage of action `mail-whois` or patch the vulnerability manually.
Data is provided by the National Vulnerability Database (NVD)
Fail2ban ≫ Fail2ban Version <= 0.9.7
Fail2ban ≫ Fail2ban Version >= 0.10.0 < 0.10.7
Fail2ban ≫ Fail2ban Version >= 0.11.0 < 0.11.3
Fedoraproject ≫ Fedora Version34
Fedoraproject ≫ Fedora Version35
Zu dieser CVE wurde keine CISA KEV oder CERT.AT-Warnung gefunden.
EPSS Metriken
Type Source Score Percentile
EPSS FIRST.org 0.3% 0.53
CVSS Metriken
Source Base Score Exploit Score Impact Score Vector string
nvd@nist.gov 8.1 2.2 5.9
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
nvd@nist.gov 6.8 8.6 6.4
AV:N/AC:M/Au:N/C:P/I:P/A:P
security-advisories@github.com 6.1 1.6 4
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:H/A:N
CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.

CWE-94 Improper Control of Generation of Code ('Code Injection')

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.