CVE-2021-45379Network attack vector

User impersonation via failed-login session overwrite

Published Dec 30, 2021 · Updated Aug 4, 2024

Improper authentication in Glewlwyd 2.0.0 through 2.6.0 allows remote authenticated users to impersonate another user. The callback_glewlwyd_user_auth handler updates an existing session with the submitted username after authentication fails instead of preserving the authenticated identity. A valid session is required; a failed login using another account's username rebinds that session to the submitted identity.

CVSS severity8.8
High
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

Improper authentication in Glewlwyd 2.0.0 through 2.6.0 allows remote authenticated users to impersonate another user. The callback_glewlwyd_user_auth handler updates an existing session with the submitted username after authentication fails instead of preserving the authenticated identity. A valid session is required; a failed login using another account's username rebinds that session to the submitted identity.

The record

CVE
CVE-2021-45379
Published
Dec 30, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-287, T1068
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 30, 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
T1068Exploitation for Privilege Escalation

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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