CVE-2026-45543: nextcloud forms
Vulnerability summary
CVE-2026-45543 is a medium (CVSS 5.3) vulnerability in nextcloud forms. EPSS estimates a 0.46% chance of exploitation in the next 30 days, higher than 38.6% of scored vulnerabilities.
Timeline
- 01-06-2026PublishedVulnerability first disclosed.
- 01-06-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS trend
Probability
0.46%
Chance of exploitation in the next 30 days
Percentile
39%
Versus all other CVEs
30-day change
+0.19 pp
From 0.27% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Nextcloud2 products
- forms≥ 4.3.0, < 5.2.7
- security-advisories≥ 4.3.0, < 5.2.7
1 vendor · 2 products
References
3 links- github.com/nextcloud/security-advisories/security/advisories/GHSA-q4fw-6jf8-5vhhX Refsource CONFIRMMitigationVendor Advisory