How severe is CVE-2021-41171?

CVE-2021-41171 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-41171 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41171?

CVE-2021-41171 affects Elabftw. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41171?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-41171 published?

CVE-2021-41171 was published on 2021-10-22 and last updated on 2026-06-17.

CVE-2021-41171

CVE-2021-41171 is a medium-severity vulnerability in Elabftw with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-307.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.0
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Elabftw
Published: 2021-10-22
Last modified: 2026-06-17

Description

eLabFTW is an open source electronic lab notebook manager for research teams. In versions of eLabFTW before 4.1.0, it allows attackers to bypass a brute-force protection mechanism by using many different forged PHPSESSID values in HTTP Cookie header. This issue has been addressed by implementing brute force login protection, as recommended by Owasp with Device Cookies. This mechanism will not impact users and will effectively thwart any brute-force attempts at guessing passwords. The only correct way to address this is to upgrade to version 4.1.0. Adding rate limitation upstream of the eLabFTW service is of course a valid option, with or without upgrading.

Frequently asked questions

What is CVE-2021-41171?: eLabFTW is an open source electronic lab notebook manager for research teams. In versions of eLabFTW before 4.1.0, it allows attackers to bypass a brute-force protection mechanism by using many different forged PHPSESSID values in HTTP Cookie header. This issue has been addressed by implementing brute force login protection, as recommended by Owasp with Device Cookies. This mechanism will not impact users and will effectively thwart any brute-force attempts at guessing passwords. The only correct way to address this is to upgrade to version 4.1.0. Adding rate limitation upstream of the eLabFTW service is of course a valid option, with or without upgrading.
How severe is CVE-2021-41171?: CVE-2021-41171 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-41171 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41171?: CVE-2021-41171 affects Elabftw. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41171?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-41171 published?: CVE-2021-41171 was published on 2021-10-22 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:elabftw:elabftw:*:*:*:*:*:*:*:*

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