CVE-2021-1404 - CVE House
Back to Database
Status published High CVE-2021-1404

Clam AntiVirus (ClamAV) Email Parser Denial of Service Vulnerability

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2021-1404

Credits & Attribution

No credits recorded in the NVD database.

References

More from Cisco

View All →
CVE-2025-20393
Cisco Secure Email Gateway and Cisco Secure Email and Web Manager Remote Command Execution Vulnerability
Critical 10
CVE-2025-20377
Cisco Unified Intelligence Center API Information Disclosure Vulnerability
Medium 4.3
CVE-2025-20376
Cisco Unified Contact Center Express Remote Code Execution Vulnerability
Medium 6.5
CVE-2025-20375
Cisco Unified Contact Center Express Arbitrary File Upload Vulnerability
Medium 6.5
CVE-2025-20374
Cisco Unified Contact Center Express Arbitrary File Download Vulnerability
Medium 4.9

Affected Vendor

Affected Software

ClamAV
Vulnerable Versions:
0.103.0, 0.103.1

Timeline

Official Publish: April 8th, 2021
Last Modified: November 8th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-20

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1059 Command and Scripting Interpreter
Execution
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1213 Data from Information Repositories
Collection
T1565.002 Stored Data Manipulation
Impact