CVE-2023-26482
CVE-2023-26482 is a critical-severity vulnerability in Nextcloud Nextcloud Server with a CVSS 3.x base score of 9.0. 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-78.
Key facts
- Severity: Critical (CVSS 3.x base score 9.0)
- EPSS exploit prediction: 4% (90th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-78
- Affected product: Nextcloud Nextcloud Server
- Published:
- Last modified:
Description
Nextcloud server is an open source home cloud implementation. In affected versions a missing scope validation allowed users to create workflows which are designed to be only available for administrators. Some workflows are designed to be RCE by invoking defined scripts, in order to generate PDFs, invoking webhooks or running scripts on the server. Due to this combination depending on the available apps the issue can result in a RCE at the end. It is recommended that the Nextcloud Server is upgraded to 24.0.10 or 25.0.4. Users unable to upgrade should disable app `workflow_scripts` and `workflow_pdf_converter` as a mitigation.
Frequently asked questions
- What is CVE-2023-26482?
- Nextcloud server is an open source home cloud implementation. In affected versions a missing scope validation allowed users to create workflows which are designed to be only available for administrators. Some workflows are designed to be RCE by invoking defined scripts, in order to generate PDFs, invoking webhooks or running scripts on the server. Due to this combination depending on the available apps the issue can result in a RCE at the end. It is recommended that the Nextcloud Server is upgraded to 24.0.10 or 25.0.4. Users unable to upgrade should disable app `workflow_scripts` and `workflow_pdf_converter` as a mitigation.
- How severe is CVE-2023-26482?
- CVE-2023-26482 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2023-26482 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-26482?
- CVE-2023-26482 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-2023-26482?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2023-26482 published?
- CVE-2023-26482 was published on 2023-03-30 and last updated on 2026-06-17.
References
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-h3c9-cmh8-7qpj
- https://github.com/nextcloud/server/commit/5a06b50b10cc9278bbe68bbf897a0c4aeb0c4e60
Affected products (2)
- cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:enterprise:*:*:*
- cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:-:*:*:*
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