CVE-2021-21234

Directory Traversal in spring-boot-actuator-logview

Workarounds

There is no workaround to fix the vulnerability other than updating or removing the dependency. However, removing read access of the user the application is run with to any directory not required for running the application can limit the impact. Additionally, access to the logview endpoint can be limited by deploying the application behind a reverse proxy.

For more information

If you have any questions or comments about this advisory:

• Open an issue in the github repo

The nature of this library is to expose a log file directory via admin (spring boot actuator) HTTP endpoints. Both the filename to view and a base folder (relative to the logging folder root) can be specified via request parameters. While the filename parameter was checked to prevent directory traversal exploits (so that filename=../somefile would not work), the base folder parameter was not sufficiently checked, so that filename=somefile&base=../ could access a file outside the logging base directory).

Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files. Typical impact: unauthorized file read or write outside the intended directory.

CVE-2021-21234 has a CVSS score of 7.7 (High). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.2.13); upgrading removes the vulnerable code path.

Kodem intelligence

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The vulnerability has been patched in release 0.2.13. Any users of 0.2.12 should be able to update without any issues as there are no other changes in that release.

1. What is CVE-2021-21234? CVE-2021-21234 is a high-severity path traversal vulnerability in eu.hinsch:spring-boot-actuator-logview (maven), affecting versions < 0.2.13. It is fixed in 0.2.13. Input manipulates file paths to reach files outside the intended directory, such as configuration or credential files.
2. How severe is CVE-2021-21234? CVE-2021-21234 has a CVSS score of 7.7 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of eu.hinsch:spring-boot-actuator-logview are affected by CVE-2021-21234? eu.hinsch:spring-boot-actuator-logview (maven) versions < 0.2.13 is affected.
4. Is there a fix for CVE-2021-21234? Yes. CVE-2021-21234 is fixed in 0.2.13. Upgrade to this version or later.
5. Is CVE-2021-21234 exploitable, and should I be worried? Whether CVE-2021-21234 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2021-21234 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2021-21234? Upgrade eu.hinsch:spring-boot-actuator-logview to 0.2.13 or later.