Use of Less Trusted Source Affecting aiohttp package, versions [,3.14.4)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-PYTHON-AIOHTTP-21280746
- published20 Oct 2026
- disclosed19 Oct 2026
- creditSyed Mohammad Ibrahim
Introduced: 19 Oct 2026
NewCVE-2026-111748 (opens in a new tab)How to fix?
Upgrade aiohttp to version 3.14.4 or higher.
Overview
Affected versions of this package are vulnerable to Use of Less Trusted Source via the HTTP request parser's handling of absolute-form request targets, where the scheme supplied in the request URL is trusted without validation. When aiohttp is used as a reverse proxy or in a configuration where it processes absolute-form requests, an attacker can send a request with a manipulated scheme in the absolute-form request-target, causing the server to use an attacker-controlled scheme value rather than the actual transport protocol scheme.