How severe is CVE-2021-3740?

CVE-2021-3740 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over an adjacent network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-3740 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3740?

CVE-2021-3740 affects Chatwoot. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3740?

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

Does CVE-2021-3740 have an EU (EUVD) identifier?

Yes. CVE-2021-3740 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-27016.

When was CVE-2021-3740 published?

CVE-2021-3740 was published on 2024-11-15 and last updated on 2026-06-17.

CVE-2021-3740

CVE-2021-3740 is a medium-severity vulnerability in Chatwoot with a CVSS 3.x base score of 6.8. 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-384.

Key facts

Severity: Medium (CVSS 3.x base score 6.8)
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-27016
Weakness: CWE-384
Affected product: Chatwoot
Published: 2024-11-15
Last modified: 2026-06-17

Description

A Session Fixation vulnerability exists in chatwoot/chatwoot versions prior to 2.4.0. The application does not invalidate existing sessions on other devices when a user changes their password, allowing old sessions to persist. This can lead to unauthorized access if an attacker has obtained a session token.

Frequently asked questions

What is CVE-2021-3740?: A Session Fixation vulnerability exists in chatwoot/chatwoot versions prior to 2.4.0. The application does not invalidate existing sessions on other devices when a user changes their password, allowing old sessions to persist. This can lead to unauthorized access if an attacker has obtained a session token.
How severe is CVE-2021-3740?: CVE-2021-3740 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over an adjacent network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-3740 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3740?: CVE-2021-3740 affects Chatwoot. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3740?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-3740 have an EU (EUVD) identifier?: Yes. CVE-2021-3740 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-27016.
When was CVE-2021-3740 published?: CVE-2021-3740 was published on 2024-11-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:chatwoot:chatwoot:*:*:*:*:*:*:*:*

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