How severe is CVE-2026-43640?

CVE-2026-43640 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-43640 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (39th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-43640?

CVE-2026-43640 affects Bitwarden Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-43640?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-43640 have an EU (EUVD) identifier?

Yes. CVE-2026-43640 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29171.

When was CVE-2026-43640 published?

CVE-2026-43640 was published on 2026-05-11 and last updated on 2026-06-17.

CVE-2026-43640

CVE-2026-43640 is a high-severity vulnerability in Bitwarden Server with a CVSS 3.x base score of 8.1. 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-303.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v4: 8.6
EPSS exploit prediction: 1% (39th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-29171
Weakness: CWE-303
Affected product: Bitwarden Server
Published: 2026-05-11
Last modified: 2026-06-17

Description

Bitwarden Server prior to v2026.4.1 does not require master-password re-authentication when retrieving or rotating an organization's SCIM API key, allowing an authenticated user with SCIM management privileges to obtain the key using only a valid session.

Frequently asked questions

What is CVE-2026-43640?: Bitwarden Server prior to v2026.4.1 does not require master-password re-authentication when retrieving or rotating an organization's SCIM API key, allowing an authenticated user with SCIM management privileges to obtain the key using only a valid session.
How severe is CVE-2026-43640?: CVE-2026-43640 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-43640 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-43640?: CVE-2026-43640 affects Bitwarden Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-43640?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-43640 have an EU (EUVD) identifier?: Yes. CVE-2026-43640 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29171.
When was CVE-2026-43640 published?: CVE-2026-43640 was published on 2026-05-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:bitwarden:server:*:*:*:*:*:*:*:*

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