How severe is CVE-2026-45543?

CVE-2026-45543 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-45543 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-45543?

CVE-2026-45543 affects Nextcloud Forms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-45543?

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

Does CVE-2026-45543 have an EU (EUVD) identifier?

Yes. CVE-2026-45543 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33713.

When was CVE-2026-45543 published?

CVE-2026-45543 was published on 2026-06-01 and last updated on 2026-06-17.

CVE-2026-45543

CVE-2026-45543 is a medium-severity vulnerability in Nextcloud Forms with a CVSS 3.x base score of 5.3. 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-552.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (19th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-33713
Weakness: CWE-552
Affected product: Nextcloud Forms
Published: 2026-06-01
Last modified: 2026-06-17

Description

Nextcloud is an open source content collaboration platform. From version 4.3.0 to before version 5.2.7, a removed collaborator retains unauthorized read access to uploaded respondent files for the affected form. The scope is limited to uploaded files for forms where that user previously had results access. This issue has been patched in version 5.2.7.

Frequently asked questions

What is CVE-2026-45543?: Nextcloud is an open source content collaboration platform. From version 4.3.0 to before version 5.2.7, a removed collaborator retains unauthorized read access to uploaded respondent files for the affected form. The scope is limited to uploaded files for forms where that user previously had results access. This issue has been patched in version 5.2.7.
How severe is CVE-2026-45543?: CVE-2026-45543 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-45543 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45543?: CVE-2026-45543 affects Nextcloud Forms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-45543?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-45543 have an EU (EUVD) identifier?: Yes. CVE-2026-45543 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33713.
When was CVE-2026-45543 published?: CVE-2026-45543 was published on 2026-06-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nextcloud:forms:*:*:*:*:*:*:*:*

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