CVE-2026-54283: CWE-770: Allocation of Resources Without Limits or Throttling in Kludex starlette
Starlette versions prior to 1.3.1 have a vulnerability where application/x-www-form-urlencoded request bodies do not enforce configured limits on the number or size of form fields. This allows an unauthenticated attacker to send arbitrarily large or numerous fields, potentially causing resource exhaustion. The issue is fixed in version 1.3.1.
AI Analysis
Technical Summary
Starlette, a lightweight ASGI framework, versions from 0.4.1 up to but not including 1.3.1 implement limits on form data parsing for multipart/form-data but silently ignore these limits for application/x-www-form-urlencoded content. This results in allocation of resources without limits or throttling (CWE-770), enabling an unauthenticated attacker to send a urlencoded body with an arbitrarily large number of fields or very large fields, potentially exhausting server resources. The vulnerability is addressed in version 1.3.1.
Potential Impact
An unauthenticated attacker can cause a denial of service by sending large or numerous urlencoded form fields that bypass configured limits, leading to resource exhaustion on the server. There is no impact on confidentiality or integrity reported.
Mitigation Recommendations
Upgrade Starlette to version 1.3.1 or later, where this vulnerability is fixed. Patch status is not explicitly stated as 'official-fix' in the advisory, but the description confirms the issue is fixed in 1.3.1. No other mitigations are indicated.
CVE-2026-54283: CWE-770: Allocation of Resources Without Limits or Throttling in Kludex starlette
Description
Starlette versions prior to 1.3.1 have a vulnerability where application/x-www-form-urlencoded request bodies do not enforce configured limits on the number or size of form fields. This allows an unauthenticated attacker to send arbitrarily large or numerous fields, potentially causing resource exhaustion. The issue is fixed in version 1.3.1.
CVSS v3.1
Score 7.5high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Starlette, a lightweight ASGI framework, versions from 0.4.1 up to but not including 1.3.1 implement limits on form data parsing for multipart/form-data but silently ignore these limits for application/x-www-form-urlencoded content. This results in allocation of resources without limits or throttling (CWE-770), enabling an unauthenticated attacker to send a urlencoded body with an arbitrarily large number of fields or very large fields, potentially exhausting server resources. The vulnerability is addressed in version 1.3.1.
Potential Impact
An unauthenticated attacker can cause a denial of service by sending large or numerous urlencoded form fields that bypass configured limits, leading to resource exhaustion on the server. There is no impact on confidentiality or integrity reported.
Mitigation Recommendations
Upgrade Starlette to version 1.3.1 or later, where this vulnerability is fixed. Patch status is not explicitly stated as 'official-fix' in the advisory, but the description confirms the issue is fixed in 1.3.1. No other mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-12T17:46:37.292Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a39735ceed863c81e39629e
Added to database: 06/22/2026, 17:39:40 UTC
Last enriched: 06/22/2026, 17:54:18 UTC
Last updated: 06/23/2026, 01:22:11 UTC
Views: 8
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