CVE-2021-43834Network attack vector

Unauthenticated impersonation of SSO-created users

Published Dec 15, 2021 · Updated Aug 4, 2024

Improper authentication in Deltablot eLabFTW before 4.2.0 allows remote attackers to impersonate users created through LDAP or SAML. The vendor has not published the affected code locus or the incorrect operation in the SSO authentication algorithm. Exposure requires LDAP or SAML authentication and an existing SSO-created account; default local-password-only instances are not affected.

CVSS severity9.1
Critical
EPSS probability0.98%
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 Deltablot eLabFTW before 4.2.0 allows remote attackers to impersonate users created through LDAP or SAML. The vendor has not published the affected code locus or the incorrect operation in the SSO authentication algorithm. Exposure requires LDAP or SAML authentication and an existing SSO-created account; default local-password-only instances are not affected.

The record

CVE
CVE-2021-43834
Published
Dec 15, 2021
Updated
Aug 4, 2024
Vendor
Deltablot
Product
eLabFTW
Classifications
CWE-287, CWE-303, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 15, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 4.2.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Deltablot · eLabFTWversion=< 4.2.0

Published CVSS scores

6.5NIST National Vulnerability DatabaseAV:N/AC:L/Au:S/C:P/I:P/A:P
9.8NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.1GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
CWE-303Incorrect Implementation of Authentication Algorithm
T1190Exploit Public-Facing Application

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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