CVE-2023-31128

CVE-2023-31128 is a high-severity vulnerability in Nextcloud Cookbook with a CVSS 3.x base score of 8.1. 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-78.

Key facts

Description

NextCloud Cookbook is a recipe library app. Prior to commit a46d9855 on the `master` branch and commit 489bb744 on the `main-0.9.x` branch, the `pull-checks.yml` workflow is vulnerable to command injection attacks because of using an untrusted `github.head_ref` field. The `github.head_ref` value is an attacker-controlled value. Assigning the value to `zzz";echo${IFS}"hello";#` can lead to command injection. Since the permission is not restricted, the attacker has a write-access to the repository. This issue is fixed in commit a46d9855 on the `master` branch and commit 489bb744 on the `main-0.9.x` branch. There is no risk for the user of the app within the NextCloud server. This only affects the main repository and possible forks of it. Those who have forked the NextCloud Cookbook repository should make sure their forks are on the latest version to prevent code injection attacks and similar.

Frequently asked questions

What is CVE-2023-31128?
NextCloud Cookbook is a recipe library app. Prior to commit a46d9855 on the `master` branch and commit 489bb744 on the `main-0.9.x` branch, the `pull-checks.yml` workflow is vulnerable to command injection attacks because of using an untrusted `github.head_ref` field. The `github.head_ref` value is an attacker-controlled value. Assigning the value to `zzz";echo${IFS}"hello";#` can lead to command injection. Since the permission is not restricted, the attacker has a write-access to the repository. This issue is fixed in commit a46d9855 on the `master` branch and commit 489bb744 on the `main-0.9.x` branch. There is no risk for the user of the app within the NextCloud server. This only affects the main repository and possible forks of it. Those who have forked the NextCloud Cookbook repository should make sure their forks are on the latest version to prevent code injection attacks and similar.
How severe is CVE-2023-31128?
CVE-2023-31128 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
Is CVE-2023-31128 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-31128?
CVE-2023-31128 affects Nextcloud Cookbook. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-31128?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-31128 published?
CVE-2023-31128 was published on 2023-05-26 and last updated on 2026-06-17.

References

Affected products (1)

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