{"id":"CVE-2026-50267","title":"Steeltoe: TLS private keys written to /tmp with default permissions, never deleted","summary":"Steeltoe: TLS private keys written to /tmp with default permissions, never deleted","severity":"medium","cvss":4.7,"cwe":["CWE-312","CWE-732"],"vendor":"Steeltoe","product":"Steeltoe.Configuration.Abstractions","ecosystem":"nuget","affected":["Steeltoe.Configuration.Abstractions >= 4.0.0, <= 4.1.0"],"patched":["Steeltoe.Configuration.Abstractions 4.2.0"],"published":"2026-07-02","updated":"2026-07-02","source":"GHSA","sourceUrl":"https://github.com/advisories/GHSA-rxrh-4j9h-xgg9","references":[{"url":"https://github.com/SteeltoeOSS/security-advisories/security/advisories/GHSA-rxrh-4j9h-xgg9"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-50267"},{"url":"https://github.com/SteeltoeOSS/Steeltoe/commit/8dd97cc6c4b184121a4bd1f92f9ac16918433471"},{"url":"https://github.com/advisories/GHSA-rxrh-4j9h-xgg9"}],"tags":["ghsa","nuget"],"epss":0.00065,"epssPercentile":0.00019,"ingestedAt":"2026-07-02T20:42:45.625Z","slug":"CVE-2026-50267","body":"## Overview\n\n### Summary\n\nWhen MySQL or PostgreSQL service bindings from `VCAP_SERVICES` include TLS client credentials, the Connectors library writes those credentials to temporary files in `Path.GetTempPath()` using `File.CreateText`. On Linux, `File.CreateText` creates files with mode `0644` (world-readable) under the process umask, and the files are never deleted. The same key material is protected at mode `0400` in `/proc/<pid>/environ`.\n\n### Impact\n\nAny process co-located in the container that runs as a different UID can read the TLS client private key from `/tmp` and use it to impersonate the application when connecting to the backing database over mutual TLS.\n\n### Affected configuration\n\n- Application is deployed on Cloud Foundry or another environment that populates `VCAP_SERVICES` with a MySQL or PostgreSQL service binding that includes `sslKey` credentials.\n- A process running as a different UID shares the container's filesystem.\n\n### Mitigations\n\nIf an immediate upgrade is not possible, prevent other processes from running in the container under a different UID with access to `/tmp`.\n\n## Affected packages\n\n- `Steeltoe.Configuration.Abstractions >= 4.0.0, <= 4.1.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `Steeltoe.Configuration.Abstractions 4.2.0`","depth":"sunlit","depthScore":26,"depthScoreParts":{"impact":25.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}