Vulnerability in io.swagger:swagger-codegen (CVE-2021-21363)
Summary
Vulnerability in io.swagger:swagger-codegen (CVE-2021-21363). Successful exploitation can lead to full system takeover. Exploitable via outputFolder. Mitigation: upgrade to 2.4.19 or later.
Original description
The description as published by the source.
Impact
On Unix like systems, the system's temporary directory is shared between all users on that system. A collocated user can observe the process of creating a temporary sub directory in the shared temporary directory and race to complete the creation of the temporary subdirectory.
This vulnerability is local privilege escalation because the contents of the outputFolder can be appended to by an attacker. As such, code written to this directory, when executed can be attacker controlled.
Java Code
The method File.createTempFile from the JDK is vulnerable to this local information disclosure vulnerability.
Patches
Fix has been applied to the master branch with:
included in release: 2.4.19
References
- CWE-378: Creation of Temporary File With Insecure Permissions
- CWE-379: Creation of Temporary File in Directory with Insecure Permissions
For more information
If you have any questions or comments about this advisory:
- Email us at security@swagger.io
Original vulnerability report
I'm performing OSS security research under t…
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2021-21363 has been found in io.swagger:swagger-codegen.
Attackers can target a specific entry point like outputFolder over the network to misuse the product.
Successful exploitation can lead to full system takeover.
What to do: upgrade io.swagger:swagger-codegen to 2.4.19 or later.
If unsure, ask your IT team or search "io.swagger:swagger-codegen CVE-2021-21363" on the vendor's site.
CVE-2021-21363 (io.swagger:swagger-codegen) — CWE-378
Attack vector: local / unauthenticated / no user interaction
Attack surface: outputFolder / File.createTempFile / delete / mkdirs
Patched: 2.4.19 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-378) exists in io.swagger:swagger-codegen. Attackers reach the vulnerable code path via outputFolder without authentication.
Check the vendor advisory for the affected versions of io.swagger:swagger-codegen. Attack surface: outputFolder / File.createTempFile / delete / mkdirs.
Severity: ?. Successful exploitation can lead to full system takeover.
Update to 2.4.19.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで io.swagger:swagger-codegen を使っているサービスとバージョンを洗い出す。
-
2Apply patch patch
Upgrade io.swagger:swagger-codegen to 2.4.19ステージング環境で 2.4.19 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- web github.com
- web github.com