CVE-2026-45409 - Medium Severity Vulnerability
Vulnerable Library - idna-3.11-py3-none-any.whl
Internationalized Domain Names in Applications (IDNA)
Library home page: https://files.pythonhosted.org/packages/0e/61/66938bbb5fc52dbdf84594873d5b51fb1f7c7794e9c0f5bd885f30bc507b/idna-3.11-py3-none-any.whl
Path to dependency file: /OPENAPI-REST-API/swagger-client/python-flask/requirements.txt
Path to vulnerable library: /tmp/ws-ua_20260402123536_MTXLIM/python_EKDBTK/202604021249581/env/lib/python3.9/site-packages/idna-3.11.dist-info
Dependency Hierarchy:
- connexion-3.3.0-py3-none-any.whl (Root Library)
- requests-2.32.5-py3-none-any.whl
- ❌ idna-3.11-py3-none-any.whl (Vulnerable Library)
Found in HEAD commit: 1f70e2feccb7006c8d32cc7d4fe62f5cf5e5c34d
Found in base branch: master
Vulnerability Details
This is the same issue as CVE-2024-3651, however the original remediation in 2024 was not a complete fix. Payloads such as ""\u0660" * N" or ""\u30fb" * N + "\u6f22"" utilize the "valid_contexto" function prior to length rejection, and for high values of "N" will take a long time to process. Impact A specially crafted argument to the "idna.encode()" function could consume significant resources. This may lead to a denial-of-service. Patches Starting in version 3.14, the function rejects long inputs as soon as practicable prior to any further processing to minimize resource consumption. In version 3.15, this approach was extended to lesser used alternate functions (i.e. per-label conversions and codec support). Workarounds Domain names cannot exceed 253 characters in length, if this length limit is enforced prior to passing the domain to the "idna.encode()" function it should no longer consume significant resources. This is triggered by arbitrarily large inputs that would not occur in normal usage, but may be passed to the library assuming there is no preliminary input validation by the higher-level application.
Publish Date: 2026-05-20
URL: CVE-2026-45409
CVSS 3 Score Details (5.3)
Base Score Metrics:
- Exploitability Metrics:
- Attack Vector: Network
- Attack Complexity: Low
- Privileges Required: None
- User Interaction: None
- Scope: Unchanged
- Impact Metrics:
- Confidentiality Impact: None
- Integrity Impact: None
- Availability Impact: Low
For more information on CVSS3 Scores, click here.
Suggested Fix
Type: Upgrade version
Origin: GHSA-65pc-fj4g-8rjx
Release Date: 2026-05-19
Fix Resolution: idna - 3.15
Step up your Open Source Security Game with Mend here
CVE-2026-45409 - Medium Severity Vulnerability
Internationalized Domain Names in Applications (IDNA)
Library home page: https://files.pythonhosted.org/packages/0e/61/66938bbb5fc52dbdf84594873d5b51fb1f7c7794e9c0f5bd885f30bc507b/idna-3.11-py3-none-any.whl
Path to dependency file: /OPENAPI-REST-API/swagger-client/python-flask/requirements.txt
Path to vulnerable library: /tmp/ws-ua_20260402123536_MTXLIM/python_EKDBTK/202604021249581/env/lib/python3.9/site-packages/idna-3.11.dist-info
Dependency Hierarchy:
Found in HEAD commit: 1f70e2feccb7006c8d32cc7d4fe62f5cf5e5c34d
Found in base branch: master
This is the same issue as CVE-2024-3651, however the original remediation in 2024 was not a complete fix. Payloads such as ""\u0660" * N" or ""\u30fb" * N + "\u6f22"" utilize the "valid_contexto" function prior to length rejection, and for high values of "N" will take a long time to process. Impact A specially crafted argument to the "idna.encode()" function could consume significant resources. This may lead to a denial-of-service. Patches Starting in version 3.14, the function rejects long inputs as soon as practicable prior to any further processing to minimize resource consumption. In version 3.15, this approach was extended to lesser used alternate functions (i.e. per-label conversions and codec support). Workarounds Domain names cannot exceed 253 characters in length, if this length limit is enforced prior to passing the domain to the "idna.encode()" function it should no longer consume significant resources. This is triggered by arbitrarily large inputs that would not occur in normal usage, but may be passed to the library assuming there is no preliminary input validation by the higher-level application.
Publish Date: 2026-05-20
URL: CVE-2026-45409
Base Score Metrics:
- Exploitability Metrics:
- Attack Vector: Network
- Attack Complexity: Low
- Privileges Required: None
- User Interaction: None
- Scope: Unchanged
- Impact Metrics:
- Confidentiality Impact: None
- Integrity Impact: None
- Availability Impact: Low
For more information on CVSS3 Scores, click here.Type: Upgrade version
Origin: GHSA-65pc-fj4g-8rjx
Release Date: 2026-05-19
Fix Resolution: idna - 3.15
Step up your Open Source Security Game with Mend here