Vulnerability report

Exploited in the wild High confidence Not in CISA KEV

CVE-2021-21234

Directory Traversal

lukashinsch / spring-boot-actuator-logview · affected before 0.2.13

Severity
CVSS 7.7 · High
Confidence
High
Exploit status
Exploited in the wild
EPSS
21.2%
First observed
Last observed

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2021-21234 is Directory Traversal affecting lukashinsch spring-boot-actuator-logview. spring-boot-actuator-logview in a library that adds a simple logfile viewer as spring boot actuator endpoint. It is maven...

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is high.

Who is affected?

lukashinsch / spring-boot-actuator-logview affected before 0.2.13.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

spring-boot-actuator-logview in a library that adds a simple logfile viewer as spring boot actuator endpoint

spring-boot-actuator-logview in a library that adds a simple logfile viewer as spring boot actuator endpoint. It is maven package "eu.hinsch:spring-boot-actuator-logview". 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. 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.

Vendor Product Affected Status
lukashinsch spring-boot-actuator-logview Before 0.2.13 Affected
Published
05 Jan 2021
Exploitation Reported
04 Jun 2026
Attack vector
Remote
Complexity
Low
Privileges
Low
User interaction
None

Tags

nuclei_scanner

CVE References

Exploitation evidence

Why KEV Intelligence marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

The Shadowserver

Recorded 04 Jun 2026

Independent exploitation attestation added to the KEV Intelligence record.

Proof of concept available

GitHub

Recorded 19 Oct 2021

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

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Source Added
The Shadowserver First 2025-06-10 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
0
User-Agents
0

Raw values available in Pro and Enterprise.

Virtual patch status

No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

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Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

7.7 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

EPSS

21.2%

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Timeline

From disclosure to observed exploitation

  1. Public PoC available

    Public proof-of-concept code published

  2. Added to KEV Intelligence KEV Feed

    High-confidence, third-party attested exploitation

  3. Nuclei template available

    Scanner coverage available

  4. CVE published

    Vulnerability disclosed publicly

  5. CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • First-party sensor telemetry
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  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2021-21234

Free JSON includes basic KEV fields
{
  "cve_id": "CVE-2021-21234",
  "confidence": "High",
  "cvss_score": 7.7,
  "cvss_estimated": false,
  "epss_score": 0.21173,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

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