CVE-2023-28847
CVE-2023-28847 is a low-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 3.1. 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-307.
Key facts
- Severity: Low (CVSS 3.x base score 3.1)
- EPSS exploit prediction: 1% (51st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-307
- Affected product: Nextcloud Nextcloud Server
- Published:
- Last modified:
Description
Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. In Nextcloud Server 24.0.0 prior to 24.0.11 and 25.0.0 prior to 25.0.5; as well as Nextcloud Server Enterprise 23.0.0 prior to 23.0.12.6, 24.0.0 prior to 24.0.11, and 25.0.0 prior to 25.0.5; an attacker is not restricted in verifying passwords of share links so they can just start brute forcing the password. Nextcloud Server 24.0.11 and 25.0.5 and Nextcloud Enterprise Server 23.0.12.6, 24.0.11, and 25.0.5 contain a fix for this issue. No known workarounds are available.
Frequently asked questions
- What is CVE-2023-28847?
- Nextcloud Server is the file server software for Nextcloud, a self-hosted productivity platform. In Nextcloud Server 24.0.0 prior to 24.0.11 and 25.0.0 prior to 25.0.5; as well as Nextcloud Server Enterprise 23.0.0 prior to 23.0.12.6, 24.0.0 prior to 24.0.11, and 25.0.0 prior to 25.0.5; an attacker is not restricted in verifying passwords of share links so they can just start brute forcing the password. Nextcloud Server 24.0.11 and 25.0.5 and Nextcloud Enterprise Server 23.0.12.6, 24.0.11, and 25.0.5 contain a fix for this issue. No known workarounds are available.
- How severe is CVE-2023-28847?
- CVE-2023-28847 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
- Is CVE-2023-28847 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-28847?
- CVE-2023-28847 primarily affects Nextcloud Nextcloud Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-28847?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2023-28847 published?
- CVE-2023-28847 was published on 2023-04-25 and last updated on 2026-06-17.
References
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-r5wf-xj97-3w7w
- https://github.com/nextcloud/server/pull/35057
- https://hackerone.com/reports/1894653
Affected products (2)
- cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*
- cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:*
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