CVE-2021-21429

Local specification disclosure via world-readable temporary files

Published Apr 27, 2021 · Updated Aug 3, 2024

Information disclosure in OpenAPI Generator Maven plugin before 5.1.0 allows local users to read temporary OpenAPI specification files. CodeGenMojo downloads a remote input specification into a file created by File.createTempFile in the shared system temporary directory, leaving default permissions readable by other users. Exposure requires a Unix-like host with a shared temporary directory; Windows and modern macOS are unaffected, and disclosed impact is limited to specification contents.

CVSS severity4.0
Medium
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in OpenAPI Generator Maven plugin before 5.1.0 allows local users to read temporary OpenAPI specification files. CodeGenMojo downloads a remote input specification into a file created by File.createTempFile in the shared system temporary directory, leaving default permissions readable by other users. Exposure requires a Unix-like host with a shared temporary directory; Windows and modern macOS are unaffected, and disclosed impact is limited to specification contents.

The record

CVE
CVE-2021-21429
Published
Apr 27, 2021
Updated
Aug 3, 2024
Vendor
OpenAPI Tools
Product
OpenAPI Generator
Classifications
CWE-379, CWE-378, CWE-377, T1005
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 27, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 5.1.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

OpenAPI Tools · OpenAPI Generatorversion=< 5.1.0

Published CVSS scores

3.3GitLab Advisory DatabaseCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
4.0GitHub Security AdvisoryCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-379Creation of Temporary File in Directory with Insecure Permissions
CWE-378Creation of Temporary File With Insecure Permissions
CWE-377Insecure Temporary File
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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