How severe is CVE-2026-43638?

CVE-2026-43638 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-43638 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-43638?

CVE-2026-43638 affects Bitwarden Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-43638?

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

Does CVE-2026-43638 have an EU (EUVD) identifier?

Yes. CVE-2026-43638 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29130.

When was CVE-2026-43638 published?

CVE-2026-43638 was published on 2026-05-11 and last updated on 2026-06-17.

CVE-2026-43638

CVE-2026-43638 is a medium-severity vulnerability in Bitwarden Server with a CVSS 3.x base score of 5.4. 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-862.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v4: 5.3
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-29130
Weakness: CWE-862
Affected product: Bitwarden Server
Published: 2026-05-11
Last modified: 2026-06-17

Description

Bitwarden Server prior to v2026.4.1 contains a missing authorization vulnerability that allows any authenticated user to write ciphers into an arbitrary organization via `POST /ciphers/import-organization` by submitting an empty `collections` array, which causes the server-side permission check to be skipped.

Frequently asked questions

What is CVE-2026-43638?: Bitwarden Server prior to v2026.4.1 contains a missing authorization vulnerability that allows any authenticated user to write ciphers into an arbitrary organization via `POST /ciphers/import-organization` by submitting an empty `collections` array, which causes the server-side permission check to be skipped.
How severe is CVE-2026-43638?: CVE-2026-43638 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-43638 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-43638?: CVE-2026-43638 affects Bitwarden Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-43638?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-43638 have an EU (EUVD) identifier?: Yes. CVE-2026-43638 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-29130.
When was CVE-2026-43638 published?: CVE-2026-43638 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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