PT-2021-2688 · Clamav+4 · Clamav+4

Published 2021-04-08 · Updated 2026-02-06 · CVE-2021-1252

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Clam AntiVirus (ClamAV) Software versions 0.103.0 and 0.103.1

Description A vulnerability in the Excel XLM macro parsing module could allow an unauthenticated, remote attacker to cause a denial of service condition on an affected device. The issue is due to improper error handling that may result in an infinite loop. An attacker could exploit this by sending a crafted Excel file to an affected device, potentially causing the ClamAV scanning process to hang.

Recommendations For versions 0.103.0 and 0.103.1, consider disabling the Excel XLM macro parsing module until a patch is available to prevent exploitation. As a temporary workaround, restrict the handling of crafted Excel files to minimize the risk of denial of service conditions. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

DoS

RCE

Infinite Loop

Weakness Enumeration

CWE-20

CWE-835

Related Identifiers

ALT-PU-2021-1627

ALT-PU-2021-1635

ALT-PU-2022-1152

BDU:2021-02219

CLEANSTART-2026-LA13761

CLEANSTART-2026-NJ87139

CLEANSTART-2026-TC95380

CLEANSTART-2026-WX01708

CVE-2021-1252

OPENSUSE-SU-2021:0555-1

OPENSUSE-SU-2021_0555-1

OPENSUSE-SU-2024:10685-1

SUSE-SU-2021:1174-1

SUSE-SU-2021:1189-1

SUSE-SU-2021:1190-1

SUSE-SU-2021:14692-1

SUSE-SU-2021_1174-1

SUSE-SU-2021_1189-1

SUSE-SU-2021_1190-1

SUSE-SU-2021_14692-1

USN-4918-1

USN-4918-2

USN-4918-3

Affected Products

Alt Linux

Clamav

Linuxmint

Suse

Ubuntu

References · 175

• https://nvd.nist.gov/vuln/detail/CVE-2017-11423 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2022-48579 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2017-12376 · Security Note
• https://cve.org/CVERecord?id=CVE-2021-1252 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2018-0361 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2023-20197 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2018-0202 · Security Note
• https://osv.dev/vulnerability/CVE-2021-1252 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-1404 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2022-20698 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2021-1252 · Vendor Advisory
• https://ubuntu.com/security/CVE-2021-1405 · Vendor Advisory
• https://osv.dev/vulnerability/CLEANSTART-2026-NJ87139 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2021:1174-1 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2017-6419 · Security Note