Clamav
CVE-2021-1252
HIGH
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V2 - Validation and Business Logic Input validation, allowlisting
|
| Impact | CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the high-severity affected system. |
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Alert meAnalysisAI
A vulnerability in the Excel XLM macro 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. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Technical ContextAI · show details
This vulnerability is classified under CWE-20. A vulnerability in the Excel XLM macro 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 error handling that may result in an infinite loop. An attacker could exploit this vulnerability by sending a crafted Excel file to an affected device. An exploit could allow the attacker to cause the ClamAV scanning process hang, resulting in a denial of service condition. Affected products include: Clamav.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
A vulnerability in the Excel XLM macro 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 error handling that may result in an infinite loop. An attacker could exploit this vulnerability by sending a crafted Excel file to an affected device. An exploit could allow the attacker to cause the ClamAV scanning process hang, resulting in a denial of service condition.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)NVD
The TAR file parser in AhnLab V3 Internet Security 2011.01.18.00, Avira AntiVir 7.11.1.163, Antiy Labs AVL SDK 2.0.3.7,
The TAR file parser in Avira AntiVir 7.11.1.163, Antiy Labs AVL SDK 2.0.3.7, avast!. Rated medium severity (CVSS 4.3), t
The RAR file parser in ClamAV 0.96.4, Rising Antivirus 22.83.00.03, Quick Heal (aka Cat QuickHeal) 11.00, G Data AntiVir
ClamAV releases prior to 0.103.0-rc fail to properly validate bytecode function names inside the ClamBC bytecode interpr
Heap-based buffer overflow in the cli_scanpe function in libclamav/pe.c in ClamAV before 0.98.5 allows remote attackers
A remote code execution vulnerability in the PDF scanning processes of ClamAV could allow an unauthenticated (CVSS 9.8).
ClamAV before 0.98.6 allows remote attackers to have unspecified impact via a crafted upack packer file, related to a "h
On Feb 15, 2023, the following vulnerability in the ClamAV scanning library was disclosed: A vulnerability in the HFS+ p
ClamAV (aka Clam AntiVirus) before 0.99.2 allows remote attackers to cause a denial of service (application crash) via a
ClamAV (aka Clam AntiVirus) before 0.99.2 allows remote attackers to cause a denial of service (application crash) via a
A vulnerability in the Portable Executable (PE) file scanning functionality of Clam AntiVirus (ClamAV) Software versions
A vulnerability in the Object Linking & Embedding (OLE2) file scanning functionality of Clam AntiVirus (ClamAV) Software
GitHub PoC
Exploit-DB