CVE-2020-9451Public exploit

Persistent service crash via predictable log hardlink

Published May 25, 2021 · Updated Aug 4, 2024

Denial of service in Acronis True Image 2020 24.5.22510 allows local users to crash anti_ransomware_service.exe after reboot. The service writes predictably named logs in a user-writable Active Protection directory without preventing a hardlink to its executable. A low-privileged local user can plant the next log-name hardlink; each reboot then triggers a sharing violation and leaves ransomware protection stopped.

CVSS severity5.5
Medium
EPSS probability0.38%
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 Acronis True Image 2020 24.5.22510 allows local users to crash anti_ransomware_service.exe after reboot. The service writes predictably named logs in a user-writable Active Protection directory without preventing a hardlink to its executable. A low-privileged local user can plant the next log-name hardlink; each reboot then triggers a sharing violation and leaves ransomware protection stopped.

The record

CVE
CVE-2020-9451
Published
May 25, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-276, T1489
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 25, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
2.1NIST NVDAV:L/AC:L/Au:N/C:N/I:N/A:P

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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-276Incorrect Default Permissions
T1489Service Stop

Public exploit references

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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