CVE-2021-32749

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Summary

CVECVE-2021-32749
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-07-16 18:15:00 UTC
Updated2023-11-07 03:35:00 UTC
Descriptionfail2ban 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.

Risk And Classification

Problem Types: CWE-94

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Fail2ban Fail2ban All All All All
Application Fail2ban Fail2ban All All All All
Operating System Fedoraproject Fedora 34 All All All
Operating System Fedoraproject Fedora 35 All All All

References

ReferenceSourceLinkTags
GNU Mailutils: unexpected processsing of escape sequences (GLSA 202310-13) — Gentoo security GENTOO security.gentoo.org
[SECURITY] Fedora 35 Update: fail2ban-0.11.2-9.fc35 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
[SECURITY] Fedora 35 Update: fail2ban-0.11.2-9.fc35 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] Fedora 34 Update: fail2ban-0.11.2-9.fc34 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
fixed possible RCE vulnerability, unset escape variable (default tild… · fail2ban/fail2ban@410a6ce · GitHub MISC github.com
[SECURITY] Fedora 34 Update: fail2ban-0.11.2-9.fc34 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
Possible RCE vulnerability in mailing action using mailutils (mail-whois) · Advisory · fail2ban/fail2ban · GitHub CONFIRM github.com
fixed possible RCE vulnerability, unset escape variable (default tild… · fail2ban/fail2ban@2ed414e · GitHub MISC github.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 179503 Debian Security Update for fail2ban (CVE-2021-32749)
  • 281997 Fedora Security Update for fail2ban (FEDORA-2021-0ab8f6a19a)
  • 501956 Alpine Linux Security Update for fail2ban
  • 502215 Alpine Linux Security Update for fail2ban
  • 503920 Alpine Linux Security Update for fail2ban
  • 690199 Free Berkeley Software Distribution (FreeBSD) Security Update for fail2ban (c848059a-318b-11ec-aa15-0800270512f4)
  • 710773 Gentoo Linux GNU Mailutils unexpected processsing of escape sequences Vulnerability (GLSA 202310-13)
  • 751147 OpenSUSE Security Update for fail2ban (openSUSE-SU-2021:1274-1)

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