CVE-2020-35556Network attack vector

Information disclosure via misconfigured notification-service CORS

Published Feb 22, 2021 · Updated Aug 4, 2024

Information disclosure in Acronis Cyber Protect before 15 Update 1 build 26172 allows remote attackers to read local notification data. The local notification service applies its cross-origin resource-sharing policy incorrectly, allowing untrusted web origins to read responses that the browser should block. Exposure is limited to information returned by that local service; no ability to modify data or interrupt protection is reported.

CVSS severity7.5
High
EPSS probability1.06%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Acronis Cyber Protect before 15 Update 1 build 26172 allows remote attackers to read local notification data. The local notification service applies its cross-origin resource-sharing policy incorrectly, allowing untrusted web origins to read responses that the browser should block. Exposure is limited to information returned by that local service; no ability to modify data or interrupt protection is reported.

The record

CVE
CVE-2020-35556
Published
Feb 22, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
Unavailable
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 22, 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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N

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

No sourced classifications are available.

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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