CVE-2021-43834: Incorrect Authentication in elabftw

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-12-16 · updated 2026-06-17
Weakness: CWE-287

Description

eLabFTW is an electronic lab notebook manager for research teams. In versions prior to 4.2.0 there is a vulnerability which allows an attacker to authenticate as an existing user, if that user was created using a single sign-on authentication option such as LDAP or SAML. It impacts instances where LDAP or SAML is used for authentication instead of the (default) local password mechanism. Users should upgrade to at least version 4.2.0.

Affected products

elabftw: before 4.2.0 — fixed in 4.2.0

How to fix

Upgrade to a fixed version: elabftw 4.2.0. Check the vendor advisory for mitigations.

References

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