# CVE-2021-21234: Spring-boot-actuator-logview - Path Traversal

> Live exploitation tracking for CVE-2021-21234 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2021-21234

## Key facts

- **Exploitation phase:** Background Noise. Continuous low-level scanning or exploitation attempts are observed, mostly opportunistic and automated.
- **CVSS score:** 7.7
- **Public exploit available:** Yes
- **Affected products:** Lukashinsch Spring-boot-actuator-logview
- **Weaknesses:** CWE-22 (Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'))
- **Tags:** web_application

## Description

Spring-boot-actuator-logview is a library that adds a simple logfile viewer as spring boot actuator endpoint. In spring-boot-actuator-logview before version 0.2.13 there is a directory traversal vulnerability. 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). 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.

## CrowdSec analysis

[CVE-2021-21234](https://euvd.enisa.europa.eu/vulnerability/CVE-2021-21234) is a directory traversal vulnerability affecting applications using the spring-boot-actuator-logview library, which exposes log file directories via HTTP endpoints. Insufficient validation of request parameters allows attackers to read files outside of the intended logging directory.

CrowdSec has been tracking this vulnerability and its exploits since 2nd of April 2025.

CrowdSec network data shows that most actors exploiting CVE-2021-21234 rely on broad, untargeted scans with minimal filtering. The activity is largely automated and opportunistic in nature.
Additionally, according to week-over-week analysis by CrowdSec, exploitation of CVE-2021-21234 is surging. Attack volumes are spiking well above historical norms, indicating widespread and escalating interest from threat actors. CVE-2021-21234 is currently experiencing high visibility and active exploitation across the internet.

Exploitation attempts are typically associated with URLs containing `/manage/log/view` or `/log/view`.

## Timeline

- 2021-01-05: CVE Published. CVE-2021-21234 is published to NVD.
- 2025-04-02: Rule Released. CrowdSec releases a rule to detect CVE-2021-21234 exploitation attempts against the CrowdSec Network.
- 2025-04-07: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2021-21234 for the first time.

## References

- https://github.com/lukashinsch/spring-boot-actuator-logview/security/advisories/GHSA-p4q6-qxjx-8jgp
- https://github.com/lukashinsch/spring-boot-actuator-logview/commit/1c76e1ec3588c9f39e1a94bf27b5ff56eb8b17d6
- https://github.com/lukashinsch/spring-boot-actuator-logview/commit/760acbb939a8d1f7d1a7dfcd51ca848eea04e772
- https://search.maven.org/artifact/eu.hinsch/spring-boot-actuator-logview
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-21234.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2021-21234) follows observed exploitation activity for CVE-2021-21234. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.