CVE-2026-84378: fallo de gravedad media en pydantic httpx2
HTTPX2: Quadratic SSE line buffering can cause CPU denial of service
Publicada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
13Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 5.9epss 0.3%
HTTPX2 is a next generation HTTP client for Python. From 2.5.0 until 2.10.0, the HTTPX2 Server-Sent Events parser in src/httpx2/httpx2/_sse.py repeatedly copies and rescans buffered text in _SSELineDecoder.decode() when an attacker-controlled or compromised SSE endpoint splits one unterminated line across many response chunks. The behavior affects httpx2.Client.sse() and httpx2.AsyncClient.sse(), and the total processing work grows quadratically with the line length, allowing a crafted stream to consume excessive CPU and block a synchronous worker or asynchronous event loop. This issue is fixed in version 2.10.0.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Productos afectados
pydantic · httpx2CVEs relacionadas — pydantic httpx2
En el mismo producto, de las más peligrosas a las menos.
CVE-2026-84382HIGHHTTPX2: Streaming response decompression does not bound peak memory (decompression amplification)EPSS 0.6%CVE-2026-84379MEDIUMHTTPX2: Multipart part header injection via unvalidated file Content-Type and custom headersEPSS 0.3%CVE-2026-84380MEDIUMHTTPX2: Conflicting Content-Length and Transfer-Encoding headers can be auto-generatedEPSS 0.2%CVE-2026-84381HIGHHTTPX2: Secure WebSocket traffic sent without TLS through SOCKS proxiesEPSS 0.1%
Referencias
https://github.com/pydantic/httpx2/commit/cbfc0e04ef6507da29ccbb3b9c2e5b23dd693414https://github.com/pydantic/httpx2/pull/1071https://github.com/pydantic/httpx2/pull/1117https://github.com/pydantic/httpx2/releases/tag/v2.10.0https://github.com/pydantic/httpx2/security/advisories/GHSA-f2fp-rgf2-35cp