CVE-2021-3181

mediumpriority · track · 27EPSS 0.028 · 87 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.83% (87th) EPSS

CVSS 4.3 · medium

Is it mine?

36 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

rfc822.c in Mutt through 2.0.4 allows remote attackers to cause a denial of service (mailbox unavailability) by sending email messages with sequences of semicolon characters in RFC822 address fields (aka terminators of empty groups). A small email message from the attacker can cause large memory consumption, and the victim may then be unable to see email messages from other persons.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

Fixedmutt-5:2.0.7-1.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-5:2.0.7-1.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-5:2.0.7-1.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-5:2.0.7-1.el8.src as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-5:2.0.7-1.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-debuginfo-5:2.0.7-1.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-debuginfo-5:2.0.7-1.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-debuginfo-5:2.0.7-1.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-debuginfo-5:2.0.7-1.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-debugsource-5:2.0.7-1.el8.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-debugsource-5:2.0.7-1.el8.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-debugsource-5:2.0.7-1.el8.s390x as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181
Fixedmutt-debugsource-5:2.0.7-1.el8.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 8)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2021:4181

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.16.5mediumAV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · Red Hat Product Security US

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-401USprimaryCWE-400USCWE-401US

affected products (36)

Products and version ranges known to be affected.

Amazon Linux 2all versionscert_bundDEcpe:/o:amazon:linux_2:-
Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Gentoo Linuxall versionscert_bundDEcpe:/o:gentoo:linux:-
Open Source Arch Linuxall versionscert_bundDEcpe:/o:archlinux:archlinux:-
Open Source muttall versionscert_bundDEcpe:/a:mutt:mutt:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
n/a n/a≤ n/aenisa_euvdEU
Michael Elkins Mutt≤ 2.0.4fstec_bduRU
АО «Концерн ВНИИНС» ОС ОН «Стрелец»≤ 16.01.2023fstec_bduRU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.1fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Common Edition≤ 2.12 «Орёл»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition≤ 1.6 «Смоленск»fstec_bduRU
ООО «РусБИТех-Астра» Astra Linux Special Edition для «Эльбрус»≤ 8.1 «Ленинград»fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 8fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 10fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 9fstec_bduRU
debian debian linux= 10.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
debian debian linux= 9.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*

showing 20 of 36

advisories (2)

Vendor and ecosystem advisories describing this.

RHSA-2021:4181Red Hat Security Advisory: mutt security, bug fix, and enhancement update2021-11-09csaf · redhat_csafUS
An update for mutt is now available for Red Hat Enterprise Linux 8. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
WID-SEC-W-2022-2240mutt: Schwachstelle ermöglicht Denial of ServiceDeutsch2021-01-19csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in mutt ausnutzen, um einen Denial of Service Angriff durchzuführen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd redhat_csaf NVD CVE.org MITRE

published 2021-01-19modified 2026-06-17

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references (42)

External citations — patches, advisories, analysis.

scry

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