CVE-2021-3856
mediumpriority · track · 17EPSS 0.012 · 67 %ileEUUSEPSS · scored 2026-10-27
ClassLoaderTheme and ClasspathThemeResourceProviderFactory allows reading any file available as a resource to the classloader. By sending requests for theme resources with a relative path from an external HTTP client, the client will receive the content of random files if available.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-3w4v-rvc4-2xpwKeycloak has Files or Directories Accessible to External Parties2022-08-27ghsa · osvUS
ClassLoaderTheme and ClasspathThemeResourceProviderFactory allows reading any file available as a resource to the classloader. By sending requests for theme resources with a relative path from an external HTTP client, the client will receive the content of random files if available.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (17)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/CVE-2021-3856cnnvd
- https://access.redhat.com/security/cve/cve-2021-3856cnnvd
- https://bugzilla.redhat.com/show_bug.cgi?id=2010164cnnvd
- https://cxsecurity.com/cveshow/CVE-2021-3856/cnnvd
- https://github.com/keycloak/keycloak/commit/73f0474008e1bebd0733e62a22aceda9e5de6743cnnvd
- https://github.com/keycloak/keycloak/pull/8588cnnvd
- https://issues.redhat.com/browse/KEYCLOAK-19422cnnvd
- https://access.redhat.com/security/cve/CVE-2021-3856enisa_euvd
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