Skip to content
Fencer Vulns
high 7.5

CVE-2021-1404 json

Clam AntiVirus (ClamAV) Email Parser Denial of Service Vulnerability

published 2021-04-08 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6871

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
2.1%
EPSS 2.1% chance of exploitation in 30 days, percentile 82%
public exploits
0
none known

Summary

A vulnerability in the PDF parsing module in Clam AntiVirus (ClamAV) Software versions 0.103.0 and 0.103.1 could allow an unauthenticated, remote attacker to cause a denial of service condition on an affected device. The vulnerability is due to improper buffer size tracking that may result in a heap buffer over-read. An attacker could exploit this vulnerability by sending a crafted PDF file to an affected device. An exploit could allow the attacker to cause the ClamAV scanning process to crash, resulting in a denial of service condition.

Patch / fix

  • clamav Debian 14, Debian 13, Debian 12 0.103.2+dfsg-1

debian advisories DEBIAN-CVE-2021-1404

  • clamav Ubuntu 16.04 LTS 0.103.2+dfsg-0ubuntu0.16.04.1
  • clamav Ubuntu 18.04 LTS 0.103.2+dfsg-0ubuntu0.18.04.1
  • clamav Ubuntu 20.04 LTS 0.103.2+dfsg-0ubuntu0.20.04.1
  • clamav Ubuntu Pro 14.04 LTS 0.103.2+dfsg-0ubuntu0.14.04.1+esm1

ubuntu advisories UBUNTU-CVE-2021-1404

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • clamav SLES for SAP 15 SP1, SLES for SAP 15, SLES 15-LTSS +11 more 0.103.2-3.26.1
  • clamav SLES for SAP 12 SP4, SLES for SAP 12 SP3, SLES 12 SP4-LTSS +8 more 0.103.2-33.35.1
  • clamav SLES 11 SP4-LTSS, SLE Point of Sale 11 SP3 0.103.2-0.20.35.1
  • clamav SLES for SAP 12 SP5, SLES 12 SP5 0.103.2-3.6.1

suse advisories SUSE-SU-2021:1190-1SUSE-SU-2021:1189-1SUSE-SU-2021:14692-1SUSE-SU-2021:1174-1

  • clamav openSUSE Tumbleweed 0.103.3-1.4
  • clamav openSUSE Leap 15.2 0.103.2-lp152.6.6.1

opensuse advisories openSUSE-SU-2024:10685-1openSUSE-SU-2021:0555-1

  • clamav Alpine 3.24, Alpine 3.23, Alpine 3.22 +11 more 0.103.2-r0

alpine advisories ALPINE-CVE-2021-1404

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • clamav Arch Linux 0.103.2-1

arch linux advisories AVG-1787

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2021-1404 updated cvss 7.5

clamav: heap buffer over-read in the email parsing module may lead to DoS

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
2 y ago

Exploit prediction

2.13% chance of exploitation in the next 30 days, higher than 82% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

  • Cisco ClamAV

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.