CVE-2026-84366
Scrapy: S3DownloadHandler sends signed S3 requests over plaintext HTTP by default
Impact
Scrapy is a high-level web crawling and scraping framework for Python. Prior to 2.17.0, in scrapy/core/downloader/handlers/s3.py, Scrapy's S3DownloadHandler converts an S3-scheme bucket and key request into a plaintext HTTP request to the corresponding S3 endpoint unless request.meta["is_secure"] is explicitly enabled, then signs and sends the plaintext request with configured AWS credentials. A network attacker who can observe traffic between Scrapy and S3 can read the bucket and key path, AWS Authorization header, X-Amz-Security-Token when temporary credentials are used, S3 object contents, and S3 response headers. An active man-in-the-middle attacker can also modify the plaintext S3 response body, status code, and headers before Scrapy processes them, causing scraped-data poisoning, poisoned exports, HTTP cache poisoning when caching is enabled, or influence over later crawl targets through forged redirects or attacker-controlled links. Users making S3-scheme requests with AWS credentials are affected. This issue is fixed in version 2.17.0.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | scrapy | < 2.17.0 | 2.17 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-76g3-c3x4-crvx
- https://github.com/scrapy/scrapy/security/advisories/GHSA-76g3-c3x4-crvx
- https://nvd.nist.gov/vuln/detail/CVE-2026-84366
- https://github.com/scrapy/scrapy/commit/9523e1ec8c41fde265a26d14563d178b6f1ad04b
- https://github.com/scrapy/scrapy/releases/tag/2.17.0