CVE-2020-8990Network attack vector

Data access via unterminated web sessions

Published Feb 20, 2020 · Updated Aug 4, 2024

Session fixation in Western Digital personal-cloud appliances before 3.6.0 allows attackers to retain account access through open web sessions. The session manager fails to terminate all open sessions after a password reset, password change, or user-account deletion. Exploitation requires access to an already authenticated browser session and exposes data reachable through that retained account session.

CVSS severity9.1
Critical
EPSS probability1.00%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Session fixation in Western Digital personal-cloud appliances before 3.6.0 allows attackers to retain account access through open web sessions. The session manager fails to terminate all open sessions after a password reset, password change, or user-account deletion. Exploitation requires access to an already authenticated browser session and exposes data reachable through that retained account session.

The record

CVE
CVE-2020-8990
Published
Feb 20, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-384, T1550.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 20, 2020CVE 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

9.1NISTCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
6.4NISTAV:N/AC:L/Au:N/C:P/I:P/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.

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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-384Session Fixation
T1550.004Use Alternate Authentication Material: Web Session Cookie

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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