https://vulnerability.circl.lu/rss/recent/all/10 Most recent entries from all 2026-09-29T06:35:38.006909+00:00 Vulnerability-Lookup info@circl.lu python-feedgen Contains only the most 10 recent entries. https://vulnerability.circl.lu/vuln/cve-2026-34520 CVE-2026-34520 — AIOHTTP: C parser (llhttp) accepts null bytes and control characters in response header values - header injection / sec… 2026-09-29T06:35:38.011568+00:00

Affected: aio-libs aiohttp

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, the C parser (the default for most installs) accepted null bytes and control characters in response headers. This issue has been patched in version 3.13.4.

 https://vulnerability.circl.lu/vuln/ghsa-63hf-3vf5-4wqf GHSA-63hf-3vf5-4wqf — AIOHTTP's C parser (llhttp) accepts null bytes and control characters in response header values - header injection/secu… 2026-09-29T06:35:38.011781+00:00

Affected: PyPI: aiohttp

### Summary

The C parser (the default for most installs) accepted null bytes and control characters in request headers.

### Impact

An attacker could send header values that are interpreted differently than expected due to the presence of control characters. For example, `request.url.origin()` may return a different value than the raw Host header, or what a reverse proxy interpreted it as., potentially resulting in some kind of security bypass.

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Patch: https://github.com/aio-libs/aiohttp/commit/9370b9714a7a56003cacd31a9b4ae16eab109ba4

 https://vulnerability.circl.lu/vuln/pysec-2026-2102 PYSEC-2026-2102 2026-09-29T06:35:38.011907+00:00

Affected: PyPI: aiohttp

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, the C parser (the default for most installs) accepted null bytes and control characters in response headers. This issue has been patched in version 3.13.4.