CVE-2024-20380Network attack vector

Scanner crash via unsafe C-Rust image handles

Published Apr 18, 2024 · Updated Aug 1, 2024

Denial of service in Cisco ClamAV 1.3.0 allows remote attackers to terminate the scanning process with crafted HTML. The HTML normalizer passes extracted CSS images through raw C-Rust FFI handles for scanning and freeing, where crafted style blocks trigger undefined behavior. The file must reach a ClamAV scan path; successful exploitation crashes the active scanner and interrupts malware inspection until the process restarts.

CVSS severity7.5
High
EPSS probability1.10%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Cisco ClamAV 1.3.0 allows remote attackers to terminate the scanning process with crafted HTML. The HTML normalizer passes extracted CSS images through raw C-Rust FFI handles for scanning and freeing, where crafted style blocks trigger undefined behavior. The file must reach a ClamAV scan path; successful exploitation crashes the active scanner and interrupts malware inspection until the process restarts.

The record

CVE
CVE-2024-20380
Published
Apr 18, 2024
Updated
Aug 1, 2024
Vendor
ClamAV
Product
ClamAV
Classifications
CWE-475, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 18, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 1, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · ClamAVversion=1.3

Published CVSS scores

7.5Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-475Undefined Behavior for Input to API
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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