CVE-2025-26790Network attack vector

Antivirus engine crash via out-of-bounds read

Published Sep 14, 2026 · Updated Sep 14, 2026

Out-of-bounds read in WithSecure Atlant before Capricorn 2025-01-20_02 allows remote attackers to crash the antivirus engine. While processing a crafted document, the Capricorn engine reads beyond a memory buffer and terminates the scanning process. Any network client able to submit a document for scanning can interrupt antivirus service; the published impact is limited to availability.

CVSS severityUnavailable
Unscored
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in WithSecure Atlant before Capricorn 2025-01-20_02 allows remote attackers to crash the antivirus engine. While processing a crafted document, the Capricorn engine reads beyond a memory buffer and terminates the scanning process. Any network client able to submit a document for scanning can interrupt antivirus service; the published impact is limited to availability.

The record

CVE
CVE-2025-26790
Published
Sep 14, 2026
Updated
Sep 14, 2026
Vendor
WithSecure
Product
WithSecure Atlant
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 14, 2026Record 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=0 <Capricorn 2025-01-20_02

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

WithSecure · WithSecure Atlantversion=0 <Capricorn 2025-01-20_02

Published CVSS scores

No CVSS assessment is available in this record.

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

T1499.004Endpoint Denial of Service: Application 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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